Four individuals with high levels of cholesterol went on a special crash diet, avoiding high-cholesterol foods and taking special supplements. Their total cholesterol levels before and after the diet were as follows:Participant Before AfterJ. K. 287 255L. M. M 305 269A. K. 243 245R. O. S. 309 247Using the .05 level of significance, was there a significant change in choles-terol level? (a) Use the steps of hypothesis testing. (b) Sketch the distributions involved. (c) Explain your answer to someone who has never taken a course in statistics.
