We want to conduct a hypothesis test of the claim that the population mean daily profit of a convenience store is more than 608 dollars. So, we record the daily profit for a random sample of days. The sample has a mean of 610 dollars and a standard deviation of 73 dollars.

For each of the following sampling scenarios, choose an appropriate test statistic for our hypothesis test on the population mean. Then calculate that statistic. Round your answers to two decimal places.

(a)The sample has size 95, and it is from a non-normally distributed population with a known standard deviation of 75.

_ z = ___

_ t = ___

_ It is unclear which test statistic to use.

(b)The sample has size 15, and it is from a normally distributed population with an unknown standard deviation.

_ z = ___

_ t = ___

_ It is unclear which test statistic to use.