The answer is the placement of the load and the placement of the force applied.
Answer:
Independent: electronics in room
Dependent: hours of sleep
Control: school nights, night routine, lighting of room, the time the person decides to go to bed
Confounding: the person(?? not entirely sure on this one)
Answer: Cardio.
Explanation: Cardio is the exercise type that burns the most calories. Running, for example, is the top exercise of calorie-burn.
