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 7.4 pounds/square inch. It is believed that the valve performs above the specifications. The valve was tested on 280 engines and the mean pressure was 7.5 pounds/square inch. Assume the variance is known to be 0.81. A level of significance of 0.05 will be used. Make a decision to reject or fail to reject the null hypothesis. Make a decision. Answer O Reject Null Hypothesis Fail to Reject Null Hypothesis Keypac Keyboard Shortcu Tables

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