You would like to construct a 99% confidence interval to estimate the population mean price of milk (per gallon) in your city. You select a random sample of prices from different stores. The sample has a mean of 3.50 dollars and a standard deviation of 0.24 dollars. (a) What is the best point estimate, based on the sample, to use for the population mean? D dollars (b) For each of the following sampling scenarios, determine which distribution should be used to calculate the critical value for the 99% confidence interval for the population mean. (In the table, 2 refers to a standard normal distribution, and t refers to a 1' distribution.) Could use Sampling scenario either Zor t Unclear The sample has size 13, and it is from a population with a 0 O 0 distribution about which we know very little. The sample has size 19, and it is from a normally distributed 0 O O 0 population with an unknown standard deviation. The sample has size 100, and it is from a non-normally distributed 0 O O 0 population with a known standard deviation of 0.27