01:30:15 An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 140 engines and the mean pressure was 5.4 pounds/square inch (psi). Assume...

Extracted text: 01:30:15 An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 140 engines and the mean pressure was 5.4 pounds/square inch (psi). Assume the population standard deviation is 1.0. If the valve was designed to produce a mean pressure of 5.6 psi, is there sufficient evidence at the 0.01 level that the valve performs below the specifications? Step 2 of 6: Find the value of the test statistic. Round your answer to two decimal places.


Extracted text: 01:30:59 An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 140 engines and the mean pressure was 5.4 pounds/square inch (psi). Assume the population standard deviation is 1.0. If the valve was designed to produce a mean pressure of 5.6 psi, is there sufficient evidence at the 0.01 level that the valve performs below the specifications? Step 1 of 6: State the null and alternative hypotheses.