With the high demand for oxygen during aerobic exercise, the need for strong responses by the cardiovascular and respiratory systems is obvious. In this section, I'd like you to make some educated guesses as to what those responses are. I'll list several factors, and I want you to tell me if they increase or decrease, or both, during aerobic exercise.     Increases   Decreases a. heart rate b. stroke volume c. cardiac output d. blood pressure e. avO2 difference f. tidal volume g. breathing rate h. minute ventilation