Whereas grading students’ homework is an important aspect of a professor’s job, reviewing homework solutions is an important ingredient in the learning process for a student. Research indicates that the longer it takes a professor to grade a homework the less likely that a student will review the homework solutions, when made available. In the past, in Professor Johnson PHYS 500 class, nonadherence on part of a few students to a prescribed HW submission format has often delayed the turnaround time for posting homework grades. In fact, in a few cases, homework’s were left ungraded till the end of the semester. Concerned about the impact this would have on student learning, the professor regularly reminded the students about the submission format, which yielded marginal positive results. Note that the time taken by the professor to grade a student's homework is normally distributed with a mean of 12.6 minutes and a standard deviation of 2.5 minutes.

1. What is the probability that a randomly selected homework will require less than 16 minutes to grade?
2. What is the probability that randomly selected homework will require more than 12 minutes to grade?
3. What is the probability that randomly selected homework will require between 11 and 15 minutes to grade?

Part A: Imagine a researcher thinks that using caffeine before a test increases test scores. If they had the consent of all the students in a 120-person class to participate in a study, a good experimental design would follow which protocol?

Part B: In a regression equation, the coefficient for the constant (aka intercept) represents,

CVP-Sensitivity analysis; spreadsheet recommended. Quality Cabinet construction is considering introducing a new cabinet-production seminar with the following price and cost characteristics.

Tution…………………………………………… $200 per Student
Variable Costs (wood, supplies, etc..)……………………. $120 per Student
Fixed Costs (advertising, instructor’s safety, insurance, etc.)………………….. $400.00 per year.

What enrollment enables Quality Cabinet construction to break even?

b. How many students will enable Quality Cabinet construction to make an operating profit of $200,000 for the year?

c. Assume that the projected enrollment for the year is 8,000 students for each of the following situations:

1. What will be the operating profit for 8,000 students?

2. What would be the operating profit if the tuition per student (that is,l sales price) decreased by 10 percent? Increased by 20 percent?

3. What should be the operating profit if variable costs per student decreased by 10 percent? Increased by 20 percent?

4. Suppose that fixed costs for the year are 10 percent lower than projected whereas variable costs per student are 10 percent higher than projected. What would be the operating profit for the year?

The owner of a small company asked a CPA to conduct an audit of the company's records. The owner of the company told the CPA that the audit was to be completed in time to submit audited financial statements to a bank as part of a loan application. The CPA immediately accepted the engagement and agreed to provide an auditor's report within three weeks. The owner agreed to pay the CPA a fixed fee plus a bonus if the load was granted. The CPA hired two accounting students to conduct the audit and spent several hours telling them exactly what to do. The CPA told the students not to spend time reviewing the internal controls but instead to concentrate on proving the mathematical accuracy of the ledger accounts and summarizing the data in the accounting records that supported the company's financial statements. The students followed the CPA's instructions and after two weeks gave the CPA the financial statements which did not include any footnotes. The CPA reviewed the statements and prepared an unmodified auditor's report. The report did not refer to GAAP or to the consistent application of GAAP. Briefly describe at least three principles underlying AICPA auditing standards and indicate how the actions of the CPA resulted in a failure to comply with each principle.

​ In a study of government financial aid for college​ students, it becomes necessary to estimate the percentage of​ full-time college students who earn a​ bachelor's degree in four years or less. Find the sample size needed to estimate that percentage. Use a 0.05 margin of error and use a confidence level of 95​%. Complete parts​ (a) through​ (c) below.

a. Assume that nothing is known about the percentage to be estimated.

___ ​(Round up to the nearest​ integer.)

b. Assume prior studies have shown that about 60​% of​ full-time students earn​ bachelor's degrees in four years or less.

___ (Round up to the nearest​ integer.)

c. Does the added knowledge in part​ (b) have much of an effect on the sample​ size?

A. No, using the additional survey information from part​ (b) only slightly reduces the sample size.

B. No, using the additional survey information from part​ (b) does not change the sample size.

C. Yes, using the additional survey information from part​ (b) only slightly increases the sample size.

D. Yes, using the additional survey information from part​ (b) dramatically reduces the sample size.

QUESTION 1  The number of customers per shop per day for a franchised business with nearly 10,000 stores nationwide is 900 people To increase the number of customers, the franchise owner is considering cutting down on the price of coffee drinks To test this new initiative, the store has reduce coffee prices in a sample of 25 stores. It is found that the mean of the number of customers per store in one day is 974 and the standard deviation is 96. At the 0.01 level, indicate whether there is significant evidence that reducing coffee prices is a good strategy to increase the mean of customers

  A study by the Pew Internet and American Life Project found that Americans have a complex and divisive attitude toward technology. This study reports that 8% of respondents are 'Omnivores,' who like gadgets, send text, make videos and upload material to YouTube. Andy believes that the percentage of students at his university 'Omnivores is greater than 8%. Andy took a sample of 200 students at his university and found that 30 students could be classified as' Omnivores. At the 0.05 level, indicate whether there is significant evidence that the percentage of Omnivores in the university is greater than 8%.

A college entrance test company determined that a score of

21

on the mathematics portion of the test suggests that a student is ready for​ college-level mathematics. To achieve this​ goal, the company recommends that students take a core curriculum of math courses in high school. Suppose a random sample of

150

students who completed this core set of courses results in a mean math score of

21.4

on the college entrance test with a standard deviation of

3.4

Do these results suggest that students who complete the core curriculum are ready for​ college-level mathematics? That​ is, are they scoring above

21

on the math portion of the​ test? Complete parts​ a) through​ d) below.

a) State the appropriate null and alternative hypotheses.

​b) Verify that the requirements to perform the test using the​ t-distribution are satisfied. Check all that apply.

​c) Use the​ P-value approach at the

alphaαequals=0.05

level of significance to test the hypotheses in part​ (a).

Identify the test statistic.

Identify the​ P-value.

​d) Write a conclusion based on the results. Choose the correct answer below.

▼

Reject

Do not reject

the null hypothesis and claim that there

▼

is not

is

sufficient evidence to conclude that the population mean is

▼

less

greater

than

21.

1. A small college went online in the middle of the semester in order avoid a virus contagion. They implemented a new online program to help increase students’ access to learning material and continue their classes. The data below is the average number of students that came to class before and after the move to online. The following is the number of students in the class before going online and after going online. The administration clams that there is no relationship between going online and the class attendance and you do not believe this. You are going to use a .10 alpha to conduct a test.

1. What is the Null and Alternative hypotheses? Write them both out below: (2)
2. What is the Critical value of the distribution? Why? (1)
3. Calculate the average difference, standard deviation for the data above: (2)
4. What is the sample statistic above? Show work (2)
5. Do we reject the null hypotheses? Is there evidence that the new system lowers the number of spoiled foods a company has? (3)

1. A community psychologist selects a sample of 16 local police officers to test whether their physical endurance is better than the median score of 72. She measures their physical endurance on a 100-point physical endurance rating scale.

Based on the data given above, compute the one-sample sign test at a 0.05 level of significance.
x =

2. A professor has a teaching assistant record the amount of time (in minutes) that a sample of 16 students engaged in an active discussion. The assistant observed 8 students in a class who used a slide show presentation and 8 students in a class who did not use a slide show presentation.

Use the normal approximation for the Mann-Whitney U test to analyze the data above. (Round your answer to two decimal places.)
z =

In an​ experiment, college students were given either four quarters or a​ $1 bill and they could either keep the money or spend it on gum. The results are summarized in the table. Complete parts​ (a) through​ (c) below.

a. Find the probability of randomly selecting a student who spent the​ money, given that the student was given four quarters.

The probability is

​(Round to three decimal places as​ needed.)

b. Find the probability of randomly selecting a student who kept the​ money, given that the student was given four quarters.

The probability is

​(Round to three decimal places as​ needed.)

c. What do the preceding results​ suggest?

A.

A student given four quarters is more likely to have kept the money than a student given a​ $1 bill.

B.

A student given four quarters is more likely to have kept the money.

C.

A student given four quarters is more likely to have spent the money than a student given a​ $1 bill.

D.

A student given four quarters is more likely to have spent the money.