PROBLEM 4 A researcher wishes to test the claim that the average cost of tuition and fees at a 4-year college is less than $6000. She selects a random sample of 64 colleges and finds the mean to be $5850. The sample standard deviation is $600. Is there evidence to support the claim at a = .01? Step 1: Hypothesis Step 2: Critical value and non-rejection range Step 3: Compute test-value (calculated z) Step 4: Reject or don't reject (explain what that means) b) Construct a 95% confidence interval. PROBLEM 5 A company that manufactures swings is interested in constructing a two-sided 90% confidence interval for the population mean of their usage time in years. They sampled 100 swings and found that the sample mean is 10 years and the sample standard deviation is 3 months (months not years)