Using computer generated regression data Clearwater State Park contracts with a refuse removal company to dispose of all the park's trash. The cost to the park is a function of the quantity of trash removed (in pounds), and the time required to load and haul it away. When trash bins overflow, the company may spend hours picking up trash bags outside of dumpsters.

The cost of service to the park has been increasing steadily over the last five years, as has been the number of people using the park. To evaluate the removal cost with park use, the park manager has randomly selected monthly data on refuse removal cost and 4 park use measures:

1. Number of park visitors 2. Number of park campers 3. Number of people using the beach locker facilities 4. Number of people renting floats and other beach items from concessions Regression analyses are presented below for each of the variables. In each case, the cost of refuse removal is the dependent variable.

REQUIRED a. Evaluate the four regression analyses and comment on value of each as a possible predictor variable for refuse removal cost. b. Calculate the estimated monthly refuse removal cost with 8,000 park visitors a month. c. Assuming a sample size of 60 and using a 95 percent confidence interval, what is the range of refuse removal costs with 8,000 park visitors a month? d. What is your answer to part c if the sample size was 25? e. Assuming a sample size of 20 and 8,000 park visitors a month, calculate the the maximum monthly refuse collection cost with a 99.5 percent confidence level.