The 10-year historical average yield of corn in the United States is about 160 bushels per acre. A survey of 50 farmers this year gives a sample mean yield of 158.4 bushels per acre. We want to know whether this is good evidence that the national mean this year is not 160 bushels per acre. Assume that the farmers surveyed are an SRS from the population of all commercial corn growers and the standard deviation of the yield in the population is = 5 bushels per acre. A. State hypotheses. B. Compute test statistic . C. Find the p-value