The lab completion times for a random sample of 30 Cal Poly students were tabulated.The sample mean is 25 minutes.The population standard deviation is believed to be 5 minutes.

The professor wants to perform a hypothesis test, with a .05 level of significance, to determine whether the completion goal of 20 minutes or less is being achieved.

a. Develop the null and alternative hypothesis

b. What is the value of the z-test?

c. What is the p-value? Please use the z-score table 1- table = p-value, use the maximum value.

d. Should we reject the null hypothesis?

e. What is the conclusion?