An engineer has designed a valve that will regulate water pressure on an automobile engine. The vahe was tested on 100 engines and the mean pressure was 72 Ibs/square inch. Assume the variance is known to be 0.81. If the valve was designed to produce a mean pressure of 73 is square inch is there sufficient evidence at
the 0.01 level that the valve does not perform to the specifications?
State the null and alternative hypotheses for the above scenario.