Please answer these questions in excel.

I need the solution in excel.

Problem 1

The average gasoline price of one of the major oil companies has been $2.20 per gallon. Because of cost reduction measures, it is believed that there has been a significant reduction in the average price. To test this belief, we randomly selected a sample of 36 of the company's gas stations and determined that the average price for the stations in the sample was $2.14. Assume that the standard deviation of the population is $0.12.

Problem 2

Officials in charge of televising an international chess competition in South America want to determine if the average time per move for the top players has remained under five minutes over the last two years. Video tapes of matches which have been played over the two years period are reviewed and a random sample of 31 moves are timed. The sample mean is 4.5 minutes with a standard deviation of 1.15 minutes. Can the officials conclude at = 0.05 that the time per move is still under 5 minutes?

Problem 3

A simple random sample of 100 postal employees is used to test if the average time postal employees have worked for the postal service has changed from the value of 7.5 years recorded 20 years ago. The sample mean was 7 years with standard deviation of 2 years Assume the distribution of the time the employees have worked for the postal service is approximately Normal. The hypothesis being tested 7.5.

a) What are the appropriate degrees of freedom for this test?

b) What is the P-value for the one-sample t test? What is your conclusion?

Problem 3 Cont.

A simple random sample of 100 postal employees is used to test if the average time postal employees have worked for the postal service has changed from the value of 7.5 years recorded 20 years ago. The sample mean was 7 years with standard deviation of 2 years Assume the distribution of the time the employees have worked for the postal service is approximately Normal. The hypothesis being tested 7.5.

C) Suppose the mean and standard deviation obtained were based on a sample of size n = 25 postal workers rather than 100. What do we know about the value of the P-value?

Problem 4

Ships arriving in US ports are inspected by customs officials for contaminated cargo. Assume, for certain ports, that 20% of the ships arriving in the previous year contained cargo that was contaminated.

A random selection of 50 ships in the current year included five that had contaminated cargo. Does the data suggest that the proportion of ships arriving in the port with contaminated cargos decreased in the current year at = 0.01?

Problem 5

The average U.S. daily internet use at home is two hours and twenty minutes. A sample of 64 homes in Soddy-Daisy showed an average usage of two hours and 50 minutes with a standard deviation of 80 minutes. We are interested in determining whether the average usage in Soddy-Daisy is significantly different from the U.S. average. Use 5% level of significance to test the hypothesis.

Problem 5

The average U.S. daily internet use at home is two hours and twenty minutes. A sample of 64 homes in Soddy-Daisy showed an average usage of two hours and 50 minutes with a standard deviation of 80 minutes. We are interested in determining whether the average usage in Soddy-Daisy is significantly different from the U.S. average. Use 5% level of significance to test the hypothesis.

Problem 6

Last year, a soft drink manufacturer had 21% of the market. To increase their portion of the market, the manufacturer has introduced a new flavor in their soft drinks. A sample of 400 individuals participated in the taste test and 100 indicated that they like the taste. We are interested in determining if more than 21% of the population will like the new soft drink.