We want to conduct a hypothesis test of the claim that the population mean germination time of strawberry seeds is different from 19.2 days. So, we choose a random sample of strawberries. The sample has a mean of 19 days and a standard deviation of 1.2 days. 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 13, and it is from a normally distributed population with an unknown standard deviation. C t= O It is unclear which test statistic to use. X 5 ? (b) The sample has size 18, and it is from a normally distributed population with a known standard deviation of 1. Oz= Ot= O It is unclear which test statistic to use