An electronics manufacturing process has historically had a mean completion time of 70 minutes. It is claimed that, due to improvements in the process, the mean completion time, u, is now less than 70 minutes. A random sample of 13 completion times using the new process is taken. The sample has a mean completion time of 65 minutes, with a standard deviation of 8 minutes.

Assume that completion times using the new process are approximately normally distributed. At the 0.05 level of significance, can it be concluded that the population mean completion time using the new process is less than 70 minutes.

Perform a one-tailed test.

a). State the null and alternative hypothesis

b). Determine the type of test statistic to use

c). Find the value of the test statistic ( round to 3 or more decimal places)

d). Find p-value (round to 3 or more decimal places)