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## What is 75% of the area of a circle with a circumference of 10 units? Round the solution to the nearest square unit.

75% of the area of the circle is 6 square units.

Step-by-step explanation:

Given:

Circumference of a circle = 10 units

Now we have to find the radius of the circle, then we have to find the area of the circle.

Circumference of a circle = 2*π*r            [π = 3.14]

2*3.14*r = 10

6.28r = 10

Dividing both side by 6.28, we get

r = 10/6.28

r = 1.59

Now let’s find the area of the circle.

The area of the circle = π*r^2

= 3.14*1.59*1.59

The area of the circle = 7.94, which is 100 %

Now we have to find the 75% of the area of the circle.

75% = 0.75

75% of the area of the circle = 0.75*7.94

= 5.95

To round off to the nearest whole number, we get 6 square units.

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## Find the general solution of the given system. dx dt = x + y ? z dy dt = 2y dy dt = y ? z

Find the general solution of the given system. dx dt = x + y ? z dy dt = 2y dy dt = y ? z

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## An 8.65-g sample of an unknown group 2a metal hydroxide is dissolved in 85.0 ml of water. an acid-base indicator is added and the resulting solution is titrated with 2.50 m hcl(aq) solution. the indicator changes color signaling that the equivalence point has been reached after 56.9 ml of the hydrochloric acid solution has been added.

The molar mass of metal hydroxide = 121.66 g/ mole

The formula is Sr(OH)2

Explanation;

M(OH)2 + 2 HCl = MCl2 + 2 H2O

Moles of the acid = 2.5 x 56.9 / 1000 = 0.14225

Therefore; moles of hydroxide at the eq point = 0.0711 moles

These have a mass of 8.65g

Thus; mass of 1 mole = 8.65 / 0.0711

= 121.66 g / mole

That means the compound is Sr (OH)2 ..

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## Which of the following would be considered a solution ? A salt in the sugar bowl B sugar added to water C oil added to water D any fat-soluble substance mixed with water soluble substance

Which of the following would be considered a solution ? A salt in the sugar bowl B sugar added to water C oil added to water D any fat-soluble substance mixed with water soluble substance

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## A 150ml sample of hydrochloric acid completely reacted with 60.0mL of a 0.100 M NaOH solution. What was the original concentration of the HCl solution

A 150ml sample of hydrochloric acid completely reacted with 60.0mL of a 0.100 M NaOH solution. What was the original concentration of the HCl solution

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## In a situation where handicapped person can only input data into the computer using a stylus or light pen, which keyboard configuration might be the solution?

In a situation where handicapped person can only input data into the computer using a stylus or light pen, which keyboard configuration might be the solution?

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## Given the system of equations, what is the solution? x + 2y = 11 x – 2y = -1 {(-5, -3)} {(1, 1)} {(5, 3)}

Given the system of equations, what is the solution? x + 2y = 11 x – 2y = -1 {(-5, -3)} {(1, 1)} {(5, 3)}

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## To determine the pH of a solution using a pH indicator, you need a? A. Color key B. neutral Solution C. Range of acids and bases

To determine the pH of a solution using a pH indicator, you need a? A. Color key B. neutral Solution C. Range of acids and bases

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## Which of the following angles is in the solution set of sec2θ – 3secθ – 2 = 0 for 0° ≤ θ < 360°

Which of the following angles is in the solution set of sec2θ – 3secθ – 2 = 0 for 0° ≤ θ < 360°

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## What kind of change occurs when salt dissolves in water a.) solution change b.) physical change c.) chemical change d.) substance change

What kind of change occurs when salt dissolves in water a.) solution change b.) physical change c.) chemical change d.) substance change

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## Why does changing the PH of a solution affect the ability of enzymes?

Why does changing the PH of a solution affect the ability of enzymes?

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## When a solution of LiC2H3O2 reacts with a solution of MgSO4, what is the net ionic equation? No reaction Mg+2 (aq) + C2H3O2- (aq) → Mg(C2H3O2)2 (s) Mg+2 (aq) + 2C2H3O2- (aq) → Mg(C2H3O2)2 (s) 2Li+ (aq) + SO4-2 (aq) → Li2SO4 (s)

I think the correct answer would be the first option. When a solution of LiC2H3O2 is mixed  with a solution of MgSO4, no reaction would be observed from the mixture. This is because magnesium cannot replace lithium from the acetate compound. Lithium is the least reactive substance based from the activity series. So, it can only react with a few substances and it does involve the reaction with magnesium sulfate. It is the very least reactive of all the alkali metals.

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## What value of x is in the solution set of 9(2x + 1)

The answer is:  ” x < -3 ” .
_____________________
Explanation:
_____________________
Given:
______________________
” 9(2x + 1)

First , factor out a “9” in the expression on the right-hand side of the inequality:

9x – 18 = 9(x – 2) ;

and rewrite the inequality:
_____________________
9(2x + 1) < 9(x – 2) ;

Now, divide EACH SIDE of the inequality by “9” ;

[9(2x + 1)] / 9 < [9(x – 2)] / 9 ;

to get:

2x + 1 < x – 2 ;

Now, subtract “x” and add “2” to each side of the inequality:

2x + 1 – x + 2  <  x – 2  – x + 2 ;

to get:

x + 3 < 0 ;

Subtract “3” from EACH SIDE ;

x + 3 – 3 < 0 – 3 ;

to get:

” x < -3 ”  .
____________________________________

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## A set of equations is given below: Equation H: y = –x + 2 Equation J: y = 3x – 4 Which of the following steps can be used to find the solution to the set of equations? (4 points) A.–x = 3x – 4 B.–x +2 = 3x C.–x + 2 = 3x – 4 D.–x + 1 = 3x + 2

A set of equations is given below: Equation H: y = –x + 2 Equation J: y = 3x – 4 Which of the following steps can be used to find the solution to the set of equations? (4 points) A.–x = 3x – 4 B.–x +2 = 3x C.–x + 2 = 3x – 4 D.–x + 1 = 3x + 2

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## The minimum and maximum temperature on a cold day in Lollypop Town can be modeled by the equation below:2|x − 6| + 14 = 38What are the minimum and maximum temperatures for this day? A:x= -9,x=21 B:X= -6,X=18 C:X=6,X= -18 D:no solution

The minimum and maximum temperature on a cold day in Lollypop Town can be modeled by the equation below:2|x − 6| + 14 = 38What are the minimum and maximum temperatures for this day? A:x= -9,x=21 B:X= -6,X=18 C:X=6,X= -18 D:no solution

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## Consider the following set of equations: Equation M: y = x + 4 Equation P: y = 3x + 6 Which of the following is a step that can be used to find the solution to the set of equations? (4 points) A. x = 3x + 6 B. x + 4 = 3x + 6 C. x + 6 = 3x + 4 D.x = 3x

Consider the following set of equations: Equation M: y = x + 4 Equation P: y = 3x + 6 Which of the following is a step that can be used to find the solution to the set of equations? (4 points) A. x = 3x + 6 B. x + 4 = 3x + 6 C. x + 6 = 3x + 4 D.x = 3x

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## f(x) = 4x f(x) = −x + 5 what is the solution

f(x) = 4x f(x) = −x + 5 what is the solution

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## What is the solution to this equation 4x+x-15+3-8x=13

What is the solution to this equation 4x+x-15+3-8x=13

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## What is the concentration of Sr2+ in a saturated solution of SrSO4? SrSO4 has a Ksp of 3.2 x 10–7

What is the concentration of Sr2+ in a saturated solution of SrSO4? SrSO4 has a Ksp of 3.2 x 10–7

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## Consider the following pair of equations: y = –2x + 8 y = x – 1 Explain how you will solve the pair of equations by substitution. Show all the steps and write the solution in (x, y) form. (5 points)

There is a special kind of substitution which some books call it by comparison.

When the two equations are both
y=some function of x
y=some other function of x, then
we can substitute the second equation into the first giving
some function of x = some other function of x and start solving.

For example,
y = –2x + 8
y = x – 1
substitute second into first
x-1=-2x+8
isolate x on left,
3x=9
x=3
second step is to substitute x=3 into second equation to get
y=x-1=3-1=2
Therefore the solution is (3,2)

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## Do you think it is always safe to pour waste chemicals and solution down the sink with lots of water? Explain.

No, it is not always safe to pour waste chemicals and solution down the sink with lots of water because it could be harmful to the environment. When you pour materials down the drain they either enter a septic system or a municipal sewer system. If the material enter a septic system, it goes into a tank buried underground where the solids settle and decompose. The rest of the wastewater is than released into a drain field where it goes into the soil. Sometimes the wastewater kills the good bacteria and can contaminate ground water or surface water.

A municipal sewer system the wastewater goes to a central sewage plant, where after treatment, it is then released into lakes, rivers and streams. Some hazardous household waste can pass through the system unchanged and pollute the waters. Also the wastewater may affect the plumbing or collect in the trap and release fumes through the drains. Most sewage facilities aren’t capable of removing such toxic substances.

So, No, it is not always safe to pour chemicals and solutions down the sink even with a lot of water.

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## I NEEED HELP PLEASEEEEEE I WILL RATE BRAINLIEST!!!!!!!!!!!! Select the properly written and balanced equation for the following chemical reaction: Aqueous solutions of sodium hydroxide and iron (III) nitrate react to produce a precipitate of iron (III) hydroxide in an aqueous solution of sodium nitrate. ——-3NaOH (aq) + Fe(NO3)3 (aq) Fe(OH)3 (s) + 3NaNO3 (aq) NaOH (aq) + FeNO3 (aq) FeOH (s) + NaNO3 (aq) NaOH (aq) + Fe(NO3)3 (aq) FeOH3 (s) + NaNO3 (aq) 3NaOH (aq) + FeNO3 (aq) FeOH (s) + 3NaNO3 (aq) I believe that it is the first choice but I am not sure….

I NEEED HELP PLEASEEEEEE I WILL RATE BRAINLIEST!!!!!!!!!!!! Select the properly written and balanced equation for the following chemical reaction: Aqueous solutions of sodium hydroxide and iron (III) nitrate react to produce a precipitate of iron (III) hydroxide in an aqueous solution of sodium nitrate. ——-3NaOH (aq) + Fe(NO3)3 (aq) Fe(OH)3 (s) + 3NaNO3 (aq) NaOH (aq) + FeNO3 (aq) FeOH (s) + NaNO3 (aq) NaOH (aq) + Fe(NO3)3 (aq) FeOH3 (s) + NaNO3 (aq) 3NaOH (aq) + FeNO3 (aq) FeOH (s) + 3NaNO3 (aq) I believe that it is the first choice but I am not sure….

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## What is the colligative property that means a solution typically has a measurably higher boiling point than a pure solvent alone? A) osmotic pressure B) boiling point elevation C) boiling point alleviation D) vapor-pressure lowering

What is the colligative property that means a solution typically has a measurably higher boiling point than a pure solvent alone? A) osmotic pressure B) boiling point elevation C) boiling point alleviation D) vapor-pressure lowering

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## What is the solution of log4x − 10^32 = 5? x = −2 x = 2 x = 3 x = 4

What is the solution of log4x − 10^32 = 5? x = −2 x = 2 x = 3 x = 4

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