State the conclusion based on the results of the test. The mean of the pressure required to open a certain valve is known to be = 7.9 psi. Due to changes in the manufacturing process, the...

State the conclusion based on the results of the test. The mean of the pressure required to open a certain valve is known to be = 7.9 psi. Due to changes in the manufacturing process, the quality-control manager feels that the average pressure has changed. The null hypothesis was rejected. Choose thee correct answer below. OA. There is not sufficient evidence that the mean of the pressure required to open a certain valve has changed. O B. The mean of the pressure has not changed. Oc. The mean of the pressure has changed. OD. There is sufficient ovidence that the mean of the pressure required to open a certain valve has changed. OE. There is sufficient evidence that the mean of the pressure required to open a certain valve has not changed. OF There is not suficient evidence that the mean of the pressure required to open a certain valve has not changed.