An engineer designed a valve that will regulate water pressure on an automobile engine. The engineer designed the valve such that it would produce a mean pressure of 7.7 lbs/square inch. The valve was tested on 140 engines and the mean pressure was 7.5 lbs/square inch. Assume the variance is known to be 0.64. Is there evidence at the 0.02level that the valve performs below the specifications?
Step 1 of 5: Enter the hypotheses: