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:
Coronary artery disease can reduce blood flow to the heart and cause heart attacks.
Explanation:
Coronary artery disease occurs when arteries suffer a blockage.
Coronary artery blockage is the main cause of heart attack since, as time passes by and due to certain substances as cholesterol, the coronary arteries undergo narrowing.
Cholesterol is the main cause of narrowing of the coronary arteries.
The answer is B.Start running in hilly areas or trails. Hope this helps!