A national chain of organic grocery stores ishoping to sell at least 1200 boxes of hemp milk per week at each store; itwill reevaluate the marketing plan if there is compelling evidence that thetrue sales figures are lower. To investigate, the chain will collect a weekof sales data from 61 randomly chosen stores. The standard deviation ofsales at each store is 260 boxes per week. a. Specify appropriate null and alternative hypotheses for this setting.
b. If the chain conducts a test with a critical value of 1150, what is the probability of a Type I error?
c. If, in addition, it turns out that the actual mean weekly sales is 1125 boxes, what is the probability of a Type II error?
d. Confirm your answers to parts (b) and (c) using the HT_errors. xlsx workbook.
e. Use the power_curves. xls workbook to sketch the power curve for the test from part (b).
f. Repeat parts (b)-(e) for the same critical value of 1150, but for a sample size of 122. Explain why your answers changed in the way that they did.