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Kate takes the elevator from the ground floor (which is labeled 0) to a floor three levels below the ground floor. Which number represents the floor where she gets off the elevator?

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Answered by answersmine AT 22/10/2019 – 02:55 AM

The number should be -3. That is because she goes from 0 to three floors bellow, meaning it’s 0-3= -3. The first floor bellow would be -1, the second would be -2, and the third one is -3. It would be different if you counted it as number 1 as they do in some countries, but here it’s -3.

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Trevor is pulling his younger brother in a wagon. He pulls the wagon 50 m to the corner with a force that is a parallel with the ground. He then turns the wagon around and pulls it 50 m back to the starting point with the same force at an angle of 30 degrees with respect to the ground. How does the amount of work Trevor performs going to the corner compare with the amount of work he performs coming back? A) they are the same because he uses the same amount of force B) they are the same because he travels the same distance C) he does less work coming back because the force moving the wagon is only 50cos30 D)he does more work coming back because the force moving the wagon is only 50cos60

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Work has the greatest value when the force done is
parallel to the direction of motion. In this case, the work done in pulling the
wagon to the corner is greater than the amount of work done in pulling the
wagon back to the starting point. This is because an angle of 30 degrees is
applied when pulling it back. The formula for work when angle is applied is:

Wx = W cos θ

Where in this case, θ = 30

Therefore,
the answer to this is letter:

C) he does less work coming back because the force moving
the wagon is only 50cos30

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A golf ball is hit from the ground with an initial velocity of 208 ft per second assume the starting height of the ball is 0 ft how long will it take the golf ball to hit the ground

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A golf ball is hit from the ground with an initial velocity of 208 ft per second assume the starting height of the ball is 0 ft how long will it take the golf ball to hit the ground

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The function H(t) = −16t2 + 48t + 12 shows the height H(t), in feet, of a cannon ball after t seconds. A second cannon ball moves in the air along a path represented by g(t) = 10 + 15.2t, where g(t) is the height, in feet, of the object from the ground at time t seconds. Part A: Create a table using integers 0 through 3 for the 2 functions. Between what 2 seconds is the solution to H(t) = g(t) located? How do you know? (6 points) Part B: Explain what the solution from Part A means in the context of the problem. (4 points)

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Given two functions: h(t)=-16t^2+48t+12 and g(t)=10+15.2t
A] The table of both functions from 0 to 3 will be:
h(t)=-16t^2+48t+12
t           0           1            2          3
h(t)       12         44          44        12

g(t)=10+15.2t

t          0        1            2             3
g(t)     10      25.2       40.4        55.6

the point in which h(t)=g(t) will be given by:
-16t^2+48t+12=10+15.2t
forming quadratic equation we get:
-16t^2+32.8t+12=0
solving the above quadratic equation using the formula we get:
t=-0.32 or t=2.4
therefore we conclude that they only met once, at point t=2.4 sec
therefore they met between points t=-0.32 and t=2.4

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An engineer on the ground is looking at the top of a building. The angle of elevation to the top of the building is 46°. The engineer knows the building is 250 ft tall. What is the distance from the engineer to the base of the building to the nearest whole foot?

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An engineer on the ground is looking at the top of a building. The angle of elevation to the top of the building is 46°. The engineer knows the building is 250 ft tall. What is the distance from the engineer to the base of the building to the nearest whole foot?

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What is the velocity of an object dropped from a height of 180 m when it hits the ground?

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What is the velocity of an object dropped from a height of 180 m when it hits the ground?

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A fence 6 feet tall runs parallel to a tall building at a distance of 5 feet from the building. what is the length of the shortest ladder that will reach from the ground over the fence to the wall of the building?

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Looks too ugly to me, but this is what I get:

First, draw the triangle of the ladder, with the fence and the building.

There are two similar right triangles: the one from the ground to the fence, and the one from the ground to the building. Let’s call L the length of the ladder and l, the length of the ladder from the ground to the fence, then:

L/(x+d) = l/x, where x is the horizontal distance from the point where the ladder touches the ground to the base of the fence and ‘d’ is the distance between the fence and the building (d=5 ft).

L = (x+d)/x*l, now l = sqrt( x^2+h^2), where h is the height of the fence (h=6 ft).

Then, one usually squares it, because the point where the maximum or minimum is attained is the same when optimizing a distance.

So that, one could look for the minimum of L^2 = (x+d)^2/x^2*(x^2+h^2), where d = 5 ft, and h = 6ft.

What I don;t like, is that L’ = dL/dx is a bit lengthy to calculate and then you have to set it = 0. I think all this is right, but I expected a somewhat simpler expression, unless you’re doing AP or similar.
 

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A boy flying a kite is standing 30 ft from a point directly under the kite. if the string to the kite is 50 ft long, what is the angle of elevation of the kite (the angle between the ground where the boy is standing and the kite string)?

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A boy flying a kite is standing 30 ft from a point directly under the kite. if the string to the kite is 50 ft long, what is the angle of elevation of the kite (the angle between the ground where the boy is standing and the kite string)?

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Which concrete detail is most relevant to Frederick Douglass’s autobiography? A. The Great House had five bedrooms and two kitchens — one inside and one outside. B. The pants Master Daniel wore most were were light gray. C. The mush was put into a large wooden tray, or trough, and set down upon the ground. D. The man who helped us ashore said we were the fifth boat to land on Smith’s Wharf that day.

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Since a tiny tender child of four,
There’s nothing that I dreamt of more,
Than to jump aboard a great big ship,
A telescope, a map, a sword, by my hip,
To feel the sea breeze in my hair,
To stroke my parrot on the wood chair,
To be bold and brave and happy as can be,
To trek and travel and sail the seven seas.

8 lines. Rhyme scheme aabbccdd. If I managed to write that in about 4 minutes, you could write something much better and longer in like 30 minutes. You can use my rubbish poem as inspiration lol. Good luck X

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Which of these excerpts from Margaret Frink’s memoir most clearly shows that her story is told in the first person? A. It was Mr. Frink’s plan to remain here until enough of the coarse grass had been cut and cured into hay to feed our horses across the desert. B. Away from the river, the soil is hard and dry, void of any vegetation except sage-brush, which is worthless for any purpose but fuel. C. The Carsons had two wagons, with four horses to each, having bought more horses at Ragtown, after losing their mules on the desert. D. There was some bare ground on the south side, but between the rocks there was plenty of snow.

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Answer:

Henri Rousseau’s Portrait of a Woman

Explanation:

Magical Realism finds precedent in eighteenth-century Gothic novels, but also connects with sixteenth-century Baroque or Surrealism, almost contemporary in the early twentieth century.

Among the most striking features of this movement, we find the blend of realism with pure unreality that is observed as normal, with the integration of magical elements without seeming extraordinary.

These works do not explain the supernatural elements and are narrated as something natural, with characters unaware of their transcendent dimension. In addition, death has paramount value in the relativistic discourse of truth, with a metaphysical focus on space and time and an intimate atmosphere that blends characters with myths, legends, and natural cultures.

Henri Rousseau’s Portrait of a Woman is considered one of the first magical realistic stories.

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Which excerpt from “The Scarlet Ibis” most foreshadows that the narrator will feel regret for something he has done to Doodle? But sometimes (like right now), as I sit in the cool, green-draped parlor, the grindstone begins to turn, and time with all its changes is ground away—and I remember Doodle. Doodle was my brother and he was going to cling to me forever, no matter what I did, so I dragged him across the burning cotton field to share with him the only beauty I knew, Old Woman Swamp. There is within me (and with sadness I have watched it in others) a knot of cruelty borne by the stream of love, much as our blood sometimes bears the seed of our destruction, and at times I was mean to Doodle. Once I had succeeded in teaching Doodle to walk, I began to believe in my own infallibility and I prepared a terrific development program for him, unknown to Mama and Daddy, of course.

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Answer:

Gather references, and prepare your résumé.

Explanation:

Before a job interview, it is advisable to prepare a copy of your résumé and references, as well as bring a pen and notepad.

The rest of the alternatives are incorrect because asking the company to keep your résumé on file is inappropriate – you should always carry a copy of  it; asking and answering questions politely happens during the course of the interview; and restating your interest is done after the interview has occurred.

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A car in dynamic equilibrium is acted upon by the following forces: force due to gravity= -9000 newtons Force due to friction = -250 newtons Forward force exerted by engine = 250 newtons. What is the value of the force exerted by the ground on the car?

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The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies. 

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface. 

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h. 

So the time for the pencil and eraser to touch is T=1.3449 hours. 

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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In which situations is gravitational potential energy present? Check all that apply. A person walks up a flight of stairs. A person runs across a room. Wind blows against a steel table anchored to the ground. Wind lifts a balloon into the air. A weightlifter holds a barbell on the ground. A weightlifter holds a barbell straight overhead

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Answer:

1) Water has very high specific heat.

2) It expands when it freezes

3) ability to dissolve in ionic substances

4) Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid.

Explanation:

1) Water molecules due to their high specific heat , undergo relatively less increase in temperature after absorbing heat. So they prevent their adjoining area to experience sharp increase in temperature.

2) Water is an example which expands on freezing. In it , large spaces are left between molecules when it cools. It happens because hydrogen bonds prevent any two molecules to come very close thereby  creating gaps. This gap is filled up when ice melts , which results in overall reduction in volume of water.

3) Uneven distribution of charge results in water molecules becoming polar in nature . A polar substance  can be dissolved in polar solvents only.

4) It is due to property of surface tension. Property  of surface tension results due to molecules of water near the surface experiencing a  net downward  force due to hydrogen bonds . It is due to fewer hydrogen bonds made by them.

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When jogging outside you accidentaly bumb into a curb. Your feet stop but your body continues to movr foward and you end up on the ground. Which law of motion is being described in this scenario?A.Law of universal gravitationB.Newton’s first law of motionC.Law of conservation of energyD. Newton’s second law of Motion

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Answer:

Velocity of plane = 30.93 m/s

Explanation:

Considering vertical motion of ball

    Initial velocity, u =  0 m/s

   Acceleration , a = 9.81 m/s²

   Displacement, s = 195 m

   We have equation of motion s= ut + 0.5 at²

   Substituting

       s= ut + 0.5 at²

       195 = 0 x t + 0.5 x 9.81 x t²

        t = 6.31 seconds

Now considering horizontal motion of ball

   Acceleration , a = 0 m/s²

   Displacement, s = 195 m

   Time, t = 6.31 s

   We have equation of motion s= ut + 0.5 at²

   Substituting

       s= ut + 0.5 at²

       195 = u x 6.31 + 0.5 x 0 x 6.31²

        u = 30.93 m/s

Velocity of plane is horizontal initial speed of ball = 30.93 m/s

Velocity of plane = 30.93 m/s

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A 100-foot ramp is tilted at a 45° angle. How high is the top of the ramp from the ground?

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The basis to respond this question are:

1) Perpedicular lines form a 90° angle between them.

2) The product of the slopes of two any perpendicular lines is – 1.

So, from that basic knowledge you can analyze each option:

a.Lines s and t have slopes that are opposite reciprocals.

TRUE. Tha comes the number 2 basic condition for the perpendicular lines.

slope_1 * slope_2 = – 1 => slope_1 = – 1 / slope_2, which is what opposite reciprocals means.

b.Lines s and t have the same slope.

FALSE. We have already stated the the slopes are opposite reciprocals.

c.The product of the slopes of s and t is equal to -1

TRUE: that is one of the basic statements that you need to know and handle.

d.The lines have the same steepness.

FALSE: the slope is a measure of steepness, so they have different steepness.

e.The lines have different y intercepts.

FALSE: the y intercepts may be equal or different. For example y = x + 2 and y = -x + 2 are perpendicular and both have the same y intercept, 2.

f.The lines never intersect.

FALSE: perpendicular lines always intersept (in a 90° angle).

g.The intersection of s and t forms right angle.

TRUE: right angle = 90°.

h.If the slope of s is 6, the slope of t is -6

FALSE. – 6 is not the opposite reciprocal of 6. The opposite reciprocal of 6 is – 1/6.

So, the right choices are a, c and g.

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Which of the following was true of life in the USSR? A. Most physicians were women. B. Women were a small minority among industrial and construction workers. C. Although women were allowed to fly fighter planes during World War II, they were banned from ground combat. D. Women achieved equality at home, and husbands were expected to share domestic duties.

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Natural Forces Affecting the Driver:

1. While the car stops, the person continues moving the way that the car were moving and then hits the obstacle in the car or the person can be thrown out of the vehicle. If the person wears belt, he will stop moving with the vehicle and won’t hit the obstacle.

2. We count approximate kinetic energy using the formula K = v^2. So the vehicle which is moving at 30 mph will have four times less kinetic energy than vehicle which is moving at 60 mph. If they have the same road conditions, the breaking distance will be four times as great for the car moving twice as fast.

3. Kinetic energy depends on object’s mass and velocity and it has direct relationship with the stopping distance. The lesser mass of the vehicle = the lesser kinetic energy and lesser stopping distance. => If both vehicles have the same velocity, then small vehicle has lesser kinetic energy than large vehicle.

4. We know that kinetic energy has this relationship with velocity K = v^2. So the best way to prepare to enter sharp curves in the roadway is to lower the speed. The most appropriate speed is 20-30 mph, but it depends on road conditions and car’s breaks condition.

5. Car crashes can happen with everyone so the best way is to be prepared. First the driver should wear a seatbelt while he’s driving. He should check his tires and breaks condition regularly. And also it’s important to slow down the vehicle while entering sharp curves. Without following these rules, the driver can get catastrophic injuries in a car crash.

Signs, Signals, and Pavement Markings: 

1. It doesn’t matter where you go. All you need is to learn highway code. It’s very different to know the meanings of every road sign. Also, it’s necessary to check your car’s conditions and you should take some spare parts for your car in case of accidents. So wherever you go, it’s important to be prepared.

2. You should stop before crossing and take few minutes to make sure there is no train approaching. If there is no train approaching, you can pass a railroad crossing. If you see approaching train, you should wait until it will pass a railroad crossing.

3. You should stop before the lights and wait to check the traffic movement and signs. Make sure that everything is safe and pass the intersection. Don’t move fast to avoid accidents.

4. Flashing yellow light means that it’s not necessary to stop but you should to pay attention on the traffic movement. So it would be better to yield before the lights and make sure if it’s safe to move. After that you can cross the intersection.

5. The line change means that the lane changes and you can’t cross solid lines. Pay more attention on road marking because it shows how you should behave on the road or highway.

6. As you approach the next exit and  your passengers need to use the restroom and get some food, you should look for green signs which indicate food and rest stops. You should to slow down if you don’t want to skip the sign.

7. When you take the exit ramp off the expressway and merge onto the next road, you see yellow lines dividing the roadway which indicates that there is oncoming traffic and this is a two-way highway. 

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When starting a foot race, a 70.0-kg sprinter exerts an average force of 650 n backward on the ground for 0.800 s. what is his final speed?

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Answer:

1) Water has very high specific heat.

2) It expands when it freezes

3) ability to dissolve in ionic substances

4) Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid.

Explanation:

1) Water molecules due to their high specific heat , undergo relatively less increase in temperature after absorbing heat. So they prevent their adjoining area to experience sharp increase in temperature.

2) Water is an example which expands on freezing. In it , large spaces are left between molecules when it cools. It happens because hydrogen bonds prevent any two molecules to come very close thereby  creating gaps. This gap is filled up when ice melts , which results in overall reduction in volume of water.

3) Uneven distribution of charge results in water molecules becoming polar in nature . A polar substance  can be dissolved in polar solvents only.

4) It is due to property of surface tension. Property  of surface tension results due to molecules of water near the surface experiencing a  net downward  force due to hydrogen bonds . It is due to fewer hydrogen bonds made by them.

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If you were to drop a rock from a tall building, assuming that it had not yet hit the ground, and neglecting air resistance, how far would it have fallen (in m) after 2 s? (g = 10 m/s2) 20.0

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The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies. 

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface. 

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h. 

So the time for the pencil and eraser to touch is T=1.3449 hours. 

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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A ball of mass 0.5 kg is released from rest at a height of 30 m. How fast is it going when it hits the ground? Acceleration due to gravity is g = 9.8 m/s²

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Answer:

1) Water has very high specific heat.

2) It expands when it freezes

3) ability to dissolve in ionic substances

4) Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid.

Explanation:

1) Water molecules due to their high specific heat , undergo relatively less increase in temperature after absorbing heat. So they prevent their adjoining area to experience sharp increase in temperature.

2) Water is an example which expands on freezing. In it , large spaces are left between molecules when it cools. It happens because hydrogen bonds prevent any two molecules to come very close thereby  creating gaps. This gap is filled up when ice melts , which results in overall reduction in volume of water.

3) Uneven distribution of charge results in water molecules becoming polar in nature . A polar substance  can be dissolved in polar solvents only.

4) It is due to property of surface tension. Property  of surface tension results due to molecules of water near the surface experiencing a  net downward  force due to hydrogen bonds . It is due to fewer hydrogen bonds made by them.

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Read the poem “There will Come Soft Rain” by Sara Teasdale (1884–1933). Which is the best restatement of the theme of the poem? There will come soft rain and the smell of the ground, And swallows circling with their shimmering sound; And frogs in the pools singing at night, And wild plum-trees in tremulous white; Robins will wear their feathery fire 5 Whistling their whims on a low fence-wire. And not one will know of the war, not one Will care at last when it is done. Not one would mind, neither bird nor tree, If mankind perished utterly. 10 And Spring herself when she woke at dawn, Would scarcely know that we were gone. Humanity needs nature to survive. Nature is the enemy of humanity. Nature will endure even if humans do not. Humans will destroy the world.

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Here are a few pointers; hope this is useful)

Ovation-by definition- is show of appreciation from an audience, for a person’s accomplishments or flaw.

“Everyone deserves a standing ovation because we all overcometh the world.”

A person’s accomplishment could be how they made a positive change in this world, strong leadership- that makes them a effective leader or simply helping others. A person’s flaw- mistakes in life, sin or even guilt should also be considered an appreciation- an ovation for representing mankind’s flaw and that humanity makes mistakes, fulfilling at least one deadly sin such as greed, lust, selfishness etc.

Thus, regardless of a person’s achievement or flaw- a person deserves an applause for, not the least, living in this society and this world that we are all living together and dying together.

That was just the introduction.. the best part is yet to come.. now it’s your turn!!

Here are other pointers to talk about in your essay:

Shakespeare’s famous line “All the World’s a stage. That agrees with your line: “Everybody deserves a standing ovation…”

Shakespeare explains that men and women are like players: they live, and die, some being celebrated and some forever living in solitude till their death. Shakespeare states the world is a “stage” which symbolizes that mankind is in its peak. The world is changing everyday: little by little and humanity is falling behind.
Due to our world turning into machinery: factories, an automotive future: where humans only job to live (entrance) and to die (exit) the famous humans remembered and the flawed not recalled.

This is according to Shakespeare’s imagery.

I don’t know what grade your in, but I think simplifying Shakespeare’s word of mouth in your essay would be handy and useful as it has strong references of your quote, and agrees strongly in your essay.

Hope this helps 🙂

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Shari was in the kitchen when she heard a crash. She went into her bedroom and found her window broken and a baseball lying on the ground. Shari said “this baseball broke my window.” This statement is an inference because she is blaming someone else for the broken window. inference because she drew a conclusion based on evidence. observation because she heard the crash before she came into the room. observation because she can see the evidence

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There are primarily three subatomic particles in an atom;
Protons
Electrons
Neutrons
—————-
Protons are positively charged subatomic particles in an atom. These particles give an element it’s identity, based on it’s ‘Atomic Number’, or how many protons are contained in the atom.

Electrons are negatively charged subatomic particles in an atom. These particles give an element it’s reactivity, and are a major part in finding where an element lies on the Periodic Table by valence electrons. We can discuss more of this in PM if you’d like to know more about this. Electrons are also a major part of finding an element’s ‘atomic mass’, or how many neutrons it has.

Neutrons are subatomic particles in an atom that have a neutral or ‘no’ charge. These are inside of the nucleus of an atom, as opposed to protons and electrons, which are farther outward of the center of an atom.

To answer your question, and reading from the text above, ‘Neutrons’ is your answer.

I hope this helps!

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Airplane releases a ball as it flies parallel to the ground at a height of 195m, the ball lands on the ground at exactly 195m from the release piont, calculate the speed v of the plane

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Answer:

a) The time the police officer required to reach the motorist was 15 s.

b) The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) The total distance traveled by the officer was 225 m.

Explanation:

The equations for the position and velocity of an object moving in a straight line are as follows:

x = x0 + v0 · t + 1/2 · a · t²

v = v0 + a · t

Where:

x = position at time t

x0 = initial position

v0 = initial velocity

t = time

a = acceleration

v = velocity at time t

a)When the officer reaches the motorist, the position of the motorist is the same as the position of the officer:

x motorist = x officer

Using the equation for the position:

x motirist = x0 + v · t (since a = 0).

x officer = x0 + v0 · t + 1/2 · a · t²

Let´s place our frame of reference at the point where the officer starts following the motorist so that x0 = 0 for both:

x motorist = x officer

x0 + v · t = x0 + v0 · t + 1/2 · a · t²      (the officer starts form rest, then, v0 = 0)

v · t = 1/2 · a · t²    

Solving for t:

2 v/a = t

t = 2 · 15.0 m/s/ 2.00 m/s² = 15 s

The time the police officer required to reach the motorist was 15 s.

b) Now, we can calculate the speed of the officer using the time calculated in a) and the  equation for velocity:

v = v0 + a · t

v = 0 m/s + 2.00 m/s² · 15 s

v = 30 m/s

The speed of the officer at the moment she overtakes the motorist is 30 m/s

c) Using the equation for the position, we can find the traveled distance in 15 s:

x = x0 + v0 · t + 1/2 · a · t²

x = 1/2 · 2.00 m/s² · (15s)² = 225 m

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A woman entering an outside glass elevator on the ground floor of a hotel glances up to the top of the building across the street and notices that the angle of elevation is 51°. she rides the elevator up three floors (60 feet) and finds that the angle of elevation to the top of the building across the street is 34°. how tall is the building across the street? (round to the nearest foot.)

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You need to determine the number of ways in which 30 competitors from 50 can qualify. First, you have to realize that the order is irrelevant, that is: it is the same competitor_1, competitor _2, competitor _3 than competitor_3, competitor_2, competitor_1, or any combination of those three competitors.

So, the number of ways is which 30 competitors from 50 can qualify is given by the formula of combinations, which is:

C (m,n) = m! / (n! * (m -n)! )

=> C (50,30) = 50! / (30! (50 – 30)! ) = (50!) / [30! (50 – 30)!] = 50! / [30! 20!] =

 = 47,129,212,243,960 different ways the qualifiying round of 30 competitors can be selected from the 50 competitors.

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