1. A Company claims that the average time a customer waits on hold is less than 5 minutes. A random sample of 28 customers shows a mean wait time of 4.78 minutes with a sample standard deviation of 1.8 minutes. Test the Company's claim at a 1% (.01) level of significance. What is your conclusion?

2. A recent newspaper story claims that less than 12% of the current U.S. workforce are union members. A random sample of 250 workers showed that 23 were union members. Test the newspaper claim at a 5% level of significance. What is your conclusion?

3. A major automobile company claims that its New electric powered car has an average range of more that 300 miles. A random sample of 40 new electric cars was selected to test the claim. Assume that the population standard deviation is 12 miles. A 5% level of significance will be used for the test.

A) What would be the consequences of making a Type II error in this problem?

B) Compute the Probability of making a Type II error if the true population mean is 305 miles.

C) What is the maximum probability of making a Type I error in this problem?

4. Report the p-value for the test in problem #2 above.