Reconsider the data from Medicine and Science in Sports and Exercise described in Exercise 8-32. The sample size was seven and the sample mean and sample standard deviation were 315 watts and 16 watts, respectively. 

(a) Is there evidence that leg strength exceeds 300 watts at significance level 0.05? Find the P-value.

(b) Compute the power of the test if the true strength is 305 watts.

(c) What sample size would be required to detect a true mean of 305 watts if the power of the test should be at least 0.90?

(d) Explain how the question in part (a) could be answered with a confidence interval.