To investigate the dependence of energy expenditure on body build, researchers used underwater weighing techniques to determine the fat-free body mass for each of seven men. They also measured the...

To investigate the dependence of energy expenditure on body build, researchers used underwater weighing techniques to determine the fat-free body mass for each of seven men. They also measured the total 24-hour energy expenditure for each man during conditions of quiet sedentary activity. The results are shown in the table. Subject Fat-free mass (kg) Energy expenditure (kcal) 1 49.3 1894 2 59.3 2050 3 68.3 2353 4 48.1 1838 5 57.6 1948 6 78.1 2528 7 76.1 2568 13 Example 5.1 a) Plot a scattergram showing the relationship between fat-free mass and energy expenditure. b) Calculate the equation of the regression line of energy expenditure on fat-free mass. Draw the regression line on the scattergram. c) Use the regression line to forecast energy expenditure for a man with fat-free mass of i. 50kg. ii. 80kg. d) Justify your answer in part (c)(ii).