You would like to construct a 90% 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 3.51 dollars and a standard deviation of 0.23 dollars. (a) What is the best point estimate, based on the sample, to use for the population mean? || dollars (b) For each of the following sampling scenarios, determine which distribution should be used to calculate the critical value for the 90% confidence interval for the population mean. (In the table, Z refers to a standard normal distribution, and t refers to a t distribution.) Could use Unclear Sampling scenario either Z ort The sample has size 13, and it is from a normally distributed population with a known standard deviation of 0.24. The sample has size 12, and it is from a normally distributed population with an unknown standard deviation. The sample has size 75, and it is from a non-normally distributed population.