A coffee dispensing machine is supposed to deliver 8 ounces of
liquid into each paper cup, but a consumer believes that the actual
amount is less. As test he obtains a sample of 36 cups of the
dispensed liquid and finds the mean content for his sample to be
7.5 ounces. If the machine operates with a standard deviation of
0.9 ounces, conduct a hypotheses test at a 0.05 level of
significance as to the content of the coffee cup.