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

4.3 pounds/square inch. It is believed that the valve performs above the specifications. The valve was tested on

26 engines and the mean pressure was

4.6 pounds/square inch with a standard deviation of

0.6. A level of significance of

0.1 will be used. Assume the population distribution is approximately normal. Make the decision to reject or fail to reject the null hypothesis.