In Example 23.3, we tested whether the average fat lost from 1 year of dieting versus 1 year of exercise was equivalent. The study also measured lean body weight (muscle) lost or gained. The average for the 47 men who exercised was a gain of 0.1 kg, which can be thought of as a loss of 20.1 kg. The standard deviation was 2.2 kg. For the 42 men in the dieting group, there was an average loss of 1.3 kg, with a standard deviation of 2.6 kg. Test to see whether the average lean body mass lost (or gained) would be different for the population of men similar to the ones in this study. Specify all four steps of your hypothesis test. (Use z instead of t.)