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A manufacturer of exercise equipment wanted to collect data on the effectiveness of their equipment. A magazine article compared how long it would take men and women to burn 200 calories during light or heavy workouts on various kinds of exercise equipment. The results summarized in the accompanying table are the average times for a group of physically active young men and women whose performances were measured on a representative sample of exercise equipment. Assume normality of the population. Complete parts (a) through (c) below. Click the icon to view the data table. a) On average, how many minutes longer than a man must a woman exercise at a light exertion rate in order to burn 200 calories? Find a 95% confidence interval. minutes (Round to one decimal place as needed.) b) Estimate the average number of minutes longer a woman must work out at a light exertion than at heavy exertion to get the same benefit. Find a 95% confidence interval. minutes (Round to one decimal place as needed.) Data table c) These data are actually averages rather than individual times. How might this affect the margins of error in these confidence intervals Choose the correct answer below. Average Minutes to Burn 200 Calories Hard Exertion Light Exertion Machine Type Men Women Men Women A. Individual times will be less variable. The standard error would be smaller, resulting in a smaller margin of error. Treadmill 13 18 14 21 X-C skier 13 16 17 22 O B. Individual times will be more variable. The standard error would be larger, resulting in a larger margin of error. Stair climber 12 18 20 37 O C. The margin of error will be unaffected. Rowing machine 15 16 22 25 Exercise rider 21 25 27 36 Exercise bike 17 19 30 44