How many calories are in a are of fat? protein? carbohydrate?

Maintaining a healthy weight allows the respiratory system to work more effectively because a. oxygen is being delivered more adequately. b. the heart does not have to pump as forcefully. c. the capillaries are constricted. d. the lung capacity allows for small amounts of air.

Alcohol is a dangerous drug because it a can change the way the mind and body function. b changes the way you look to other people. c makes you believe you are invincible. d cannot absorb into the bloodstream.

The dietary guidelines for americans recommend (a) avoiding smoking. (b) engaging in aerobic exercise for 60 minutes at least five days a week. (c) making all of your grain choices whole grains. (d) increasing your intake of fruits and vegetables.