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A random sample of 25 statistics examinations was taken. the average score in the sample was 76 with a standard deviation of 12. assuming the scores are normally distributed, the 99% confidence interval for the population average examination score is:

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Since the sample size is less than 30, therefore we use
the t statistic.

Let us define the given variables:

N = sample size = 25

X = average score = 76

s = standard deviation = 12

99% Confidence interval

Degrees of freedom = n – 1 = 24

 

The formula for confidence interval is given as:

CI = X ± t * s / sqrt N

 

using the standard distribution table, the t value for DF
= 24 and 99% CI is:

t = 2.492

 

Therefore calculating the CI using the known values:

CI = 76 ± 2.492 * 12 / sqrt 25

CI = 76 ± 5.98

CI = 70.02, 81.98

 

Answer: The average score ranges from 70 to 82.

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Which statement is true? A sample statistic can never be equal to the population parameter. Point estimates are defined for both samples and populations. To calculate a sample proportion, we need to know the population size. To calculate a point estimate, we need to know the sample size

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Answer:

Option C is true. To calculate a sample proportion, we need to know the population size.

Step-by-step explanation:

To calculate a sample proportion, we need to know the population size. – This is the true statement.

A sample statistic can never be equal to the population parameter. This is false. A statistic is a feature of sample and a parameter is a feature of  population. Every sample of the selected size has an equal chance of being used.

Point estimates are defined for both samples and populations. This is false. A point estimate is used to estimate the population parameter.

To calculate a point estimate, we need to know the sample size. This is false. Population is needed.

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The percentage of the total population living below the poverty level is known as the A. income rate. B. poverty rate. C. poor rate. D. poverty measure.

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The percentage of the total population living below the poverty level is known as the A. income rate. B. poverty rate. C. poor rate. D. poverty measure.

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Which technology is used on farms to increase food production for the growing human population

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Answer:

Genetic engineering.

Explanation:

Genetic engineering is a technology that involves recombinant DNA or RNA, through the genetic code, widely used by industrial agriculture. Through technology, the DNA of many plants has been modified so that crops are better protected against disease and pests, increase their resistance to unfavorable environmental conditions (such as drought and frost) and increase their reproductive rate. This has made crops produce more, the result of this is increased food production for the growing human population.

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What price do farmers get for the peach crops? in the third week of June, a random sample of 40 farming regions gave a sample mean of $6.88 per basket. assume that the standard deviation is known to be $1.92 per basket. find a 90% confidence interval for the population mean price per basket that farmers in this region get for their peach crop

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Given:
Sample size, n = 40
Sample mean, xb = $6.88
Population std. deviation, σ = $1.92 (known)
Confidence interval = 90%

Assume normal distribution for the population.
The confidence interval is
(xb + 1.645*(σ/√n), xb – 1.645*(σ/√n)
= (6.88 + (1.645*1.92)/√40, 6.88 – (1.645*1.92)/√40)
= (7.38, 6.38)

Answer: The 90% confidence interval is (7.38, 6.38)

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Consider college officials in admissions registration, counseling, financial aid campus ministry, food services, and so on. How much money do these people make each year? Suppose you read in your local newspaper that 45 officials in student services earn an average of $50,340 each year. Assume that the standard deviation is $10,780 for salaries of college officials and student services. Find a 90% confidence interval for the population mean salaries of such personnel. Round your answer to the nearest dollar and don;t forget to use the $ sign.

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Since sample size is > 40, we use the z-score
in calculating for the confidence interval.

The formula is given as:

Confidence Interval = X ± z * σ / sqrt (n)

Where,

X = mean = $50,340

z = z-score which is taken from standard distribution
tables at 90% confidence interval = 1.645

σ
= standard deviation = $10,780

n = sample size = 45

Substituting to the equation:

Confidence Interval = 50,340 ± 1.645 * 10,780 / sqrt (45)

Confidence Interval = 50,340 ± 1,607

Confidence Interval = $48,733 to $51,947

Therefore the salary range of the personnel is $48,733 to $51,947.

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What factors led to population growth in the high middle ages?

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What factors led to population growth in the high middle ages?

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About what percentage of the counties in Arizona have a population of less than 4–12 people per square mile?

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About what percentage of the counties in Arizona have a population of less than 4–12 people per square mile?

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Samples of size n = 90 are randomly selected from the population of numbers (0 through 9) produced by a random-number generator, and the variance is found for each sample. What is the distribution of the sample variances?

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Answer:

chi square distribution with df = n-1

Step-by-step explanation:

Given that sample of size n=90  are randomly selected from the population of numbers (0 through 9) produced by a random-number generator

Since sample size is large and randomness is followed we can assume that the variable follows a normal distribution.

Hence the sample variance would follow a chi square distribution with degree of freedom = n-1\=89

This is because we have frac{x-mu}{sigma} is standard normal hence square will be a chisquare variate.  When we sum n variates we get chi square distribution with df n-1

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In Texas, the population of a species of bats is decreasing at a rate of -0.121 per year. The population was 34,000 in 2000. According to the function; A(t) = A0e^(kt), what is the predicted population in 2015?

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Answer:

Population of bats in year 2015 is 5536.

Step-by-step explanation:

The given function A(t) = A_{0}e^{-kt} predicts the population of bats after t years.

Here A(t) = population after ‘t’ years

           k  = growth constant

           t = time in years

          A_{0} = initial population

In year 2000 population of bats A(t) = 34,000

Since rate of decrease in population k = 0.121 per year

So population in 2015 will be

A(t) A_{0}e^{(-0.121)(15)}

= 34,000 [ e^{-1.815} ]

= 34,000 ( 0.162837)

= 5536 bats

Therefore, population of bats in year 2015 is 5536.

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Geographers rank human settlements based on what two factors? A. population and size by area B. size by area and impact/importance to the region C. population and impact/importance to the region D. population and growth rate **THE ANSWER IS C. POPULATION AND IMPACT/IMPORTANCE TO THE REGION**

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Geographers rank human settlements based on what two factors? A. population and size by area B. size by area and impact/importance to the region C. population and impact/importance to the region D. population and growth rate **THE ANSWER IS C. POPULATION AND IMPACT/IMPORTANCE TO THE REGION**

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Which principle states that two species in the same habitat cannot have the same niche? niche exclusion principle competitive exclusion principle habitat exclusion principle population exclusion principle

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Answer: competitive exclusion principle

The competitive exclusion principle suggests that no two species can occupy the same ecological niche (functional role an organism performs in an ecosystem like type of food, and habitat chosen for living) in the ecosystem, the one which is stronger and superior over the other is likely to derive the resources and exhibit better chances of survival.  

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Two different species in the same ecosystem can share a _____. population habitat carrying capacity niche

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Two different species in the same ecosystem can share a _____. population habitat carrying capacity niche

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Which was an advantage for the north at the start of the Civil War a large population they will lead army few were railroads a fighting spirit

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Which was an advantage for the north at the start of the Civil War a large population they will lead army few were railroads a fighting spirit

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Which of the following is an example of microevolution? A caterpillar changes form into a butterfly. A population of birds slowly changes feather color from red to blue. A dinosaur species evolves over time into a bird species. A black cat has kittens with white spots.

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Which of the following is an example of microevolution? A caterpillar changes form into a butterfly. A population of birds slowly changes feather color from red to blue. A dinosaur species evolves over time into a bird species. A black cat has kittens with white spots.

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An animal shelter has 18 puppies. If the puppies are 36% of the total dog and cat population, how many dogs and cats are in the animal shelter?

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An animal shelter has 18 puppies. If the puppies are 36% of the total dog and cat population, how many dogs and cats are in the animal shelter?

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What is a biological control for pest management? a. some members of the pest population are sterilized b. sexual attractants lure pest species to traps c. predators, parasites, or disease organisms are released to reduce pest populations d. harvested foods are exposed to ionizing radiation e. genetic engineering develops pest-resistant crops?

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What is a biological control for pest management? a. some members of the pest population are sterilized b. sexual attractants lure pest species to traps c. predators, parasites, or disease organisms are released to reduce pest populations d. harvested foods are exposed to ionizing radiation e. genetic engineering develops pest-resistant crops?

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Which list correctly orders events in the rise and fall of apartheid in South Africa? i. Nelson Mandela became the nation’s president. ii. The Soweto Uprising sparked more protests. iii. Frederik W. de Klerk brought about reforms. iv. The Population Registration Act was signed. i. The Population Registration Act was signed. ii. Nelson Mandela became the nation’s president. iii. The Soweto Uprising sparked more protests. iv. Frederik W. de Klerk brought about reforms. i. The Population Registration Act was signed. ii. The Soweto Uprising sparked more protests. iii. Frederik W. de Klerk brought about reforms. iv. Nelson Mandela became the nation’s president. i. Frederik W. de Klerk brought about reforms. ii. Nelson Mandela became the nation’s president. iii. The Population Registration Act was signed. iv. The Soweto Uprising sparked more protests.

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The Reformation actually started after Columbus’s landing in North America. 

Treaty of Tordesillas in 1494 was forced on Spain and Portugal by the Pope. The Pope basically said that all lands in the New World belonged to Spain and all new non-Christian lands in the Eastern Hemisphere belong to Portugal. No other Catholic countries can do anything in those areas without the approval of the owner. 

The pope basically drew two lines on the globe setting the border. The western line started at the north pole cut half way through Greenland and ended at the south pole. The new world was everything to the west. Problem is that it ran through a chunk of Brazil which is why Brazil is an ex-Portuguese colony. 

The Eastern line starts at the North Pole runs through siberia, through the pacific just west of Japan, and cuts Australia in half. Of course, Australia hadn’t been discovered yet. Everything to the the east of this line is the new world. 

Obviously, this treaty didn’t hold up well, but the reformation gave the protestant countries an excuse to explore the new world since they didn’t have to take orders from the Pope. Even so, France, a catholic country, ignored it too. 

Really, the only country that was effected by the reformation in the exploration of the Americas was England. All the other countries, changed their religion once and then went to war with the nearest catholic country. Sweden became Lutheran and stayed that way. The Dutch Republic became Calvinists and stayed that way. 

England kept switching. First it was Catholic. Then, Henry VIII made it protestant. Then, Henry’s daughter Mary I made it catholic again. Henry’s other daughter Elizabeth I (with the two hit movies) made it Protestant again. 

Years latter, Oliver Cromwell over through the monarchy, executed the King Charles I, and established a Protestant fundamentalist religious military dictatorship. He outlawed drinking,smoking, gambling, theater, dirty books, sports, prostitution, and anything generally fun. He would have made Saudi Arabia proud. Basically, all you could do is work, pray, and die. Sex was allowed for creating children, but you couldn’t enjoy it. 

When Cromwell died, the people of England said enough was enough and brought back the King. Charles II kicked out the fundamentalists and brought back drinking, smoking, gambling, dirty books, sports, prostitution, and having fun during sex. Incidentally, those were also all his hobbies. 

This brings us to the famous Pilgrims. They were part of Cromwell’s crowd. They kept agitating a return to the no-fun policy. They annoyed everybody. They weren’t persecuted for practicing their religion, they were persecuted because they kept trying to force their religion on everyone else. Sort of like Southern Baptists. 

Charles II was the most easy going monarch in British history. Do realize how annoying you have to be to get him to throw you out. 

Charles’s brother James II was obsessed with turning Great Britain catholic again. After four years of trying, they kicked him and his followers out. 

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Find the sample standard deviation and the population standard deviation of the data set. 70, 58, 70, 37, 58, 47, 58, 76, 77, 67, 66, 77, 33, 74, 57

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Employee                                 Mary      Zoe         Greg         Ann           Tom

Cumulative Pay                       $6,800   $10,500  $8,400    $66,000   $4,700

Pay subject to FICA S.S.         $421.60  $651.00  $520.80 $4092.00 $291.40
6.2%, (First $118,000)

Pay subject to FICA Medicare $98.60 $152.25    $121.80    $957.00    $68.15
1.45% of gross

Pay subject to FUTA Taxes      $40.80  $63.00     $50.40    $396.00  $28.20
0.6%

Pay subject to SUTA Taxes   $367.20  $567.00  $453.60  $3564.00 $253.80
5.4% (First $7000)

Totals                                     $928.20 $1,433.25 $1,146.60 $9,009.00 $641.55

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WILL GIVE BRAINIEST ANSWER ASAP 1. Africa’s population is growing very quickly. 2. Much of the best land in Africa is being used to grow cash crops, such as coffee, for export to other countries. 3. Droughts are common in Africa. Which of the following problems are the governments of Africa most likely to be concerned about as a result of the conditions above? A. increased risk of famine B. lower poverty rates C. higher education attendance D. lower rates of disease

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Answer:

The answer is C. In order to carefully control conditions and confirm or disconfirm a hypothesis about the causes of behavior, one must perform an experiment.

Explanation:

Experimental research allows the researcher to control all the variables in order to create the conditions that can confirm or disconfirm a hypothesis. This method aimes to establish a relation of causality between two variables, which means that one variable is generated and determined by the other; this is posible because all of the other variables that can influence it have been controlled.

When a researcher conducts a survey or engages in naturalistic observation, he can’t control the variables, therefore, he can only establish a correlation between two variables, but not of causality.

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Which lines from Lincoln’s Second Inaugural Address appeal to pathos? Check all that apply. [A]ll thoughts were anxiously directed to an impending civil war. All dreaded it, all sought to avert it. One-eighth of the whole population were colored slaves, not distributed generally over the Union, but localized in the southern part of it. Neither anticipated that the cause of the conflict might cease with or even before the conflict itself should cease. Fondly do we hope, fervently do we pray, that this mighty scourge of war may speedily pass away. Neither party expected for the war the magnitude or the duration which it has already attained.

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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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A country’s population in 1992 was 72 million. In 1998 it was 76 million. Estimate the population in 2012 using the exponential growth formula. Round your answer to the nearest million.P=Ae^kt

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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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By 1850, 15 percent of the total U.S. population lived in cities. Please select the best answer from the choices provided T F

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It is called SAFETY. According to Maslow’s hierarchy of
needs (a motivational theory covering a five level model of human needs), humans
need safety. It includes protection from elements, security, order, law,
stability, freedom from fear. Safety needs is considered as basic needs along
with the physiological needs. 

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By 1850, 15 percent of the total U.S. population lived in cities. Please select the best answer from the choices provided T F

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It is called SAFETY. According to Maslow’s hierarchy of
needs (a motivational theory covering a five level model of human needs), humans
need safety. It includes protection from elements, security, order, law,
stability, freedom from fear. Safety needs is considered as basic needs along
with the physiological needs. 

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A math teacher wants to find out the average number of hours his students spend working on their math homework for his class each week. Which group would best represent a sample of the population? the first 30 students who enter the school building one morning 30 students selected from the lunchroom 30 students selected from his class rosters 30 students who stay after school for football practice

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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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