A concrete mix is being designed to provide adequate compressive strength for concrete blocks. The specification for a particular application calls for the blocks to have a mean compressive strength μμ is greater than 1450 kPa. A sample of 96 blocks is produced and tested. Their mean compressive strength is 1455.3 kPA, their standard deviation is 73.65 kPa. A test is made of (use α=0.05α=0.05 )

a) Do you believe it is plausible that the blocks do not meet the specification, or are you convinced that they do? Explain your reasoning by carrying out the appropriate hypothesis test.

b) If a sample of 10 blocks is produced and tested with their mean compressive strength at 1372 kPa and their standard deviation at 68 kPa. Find the P-value based on the same hypothesis.