The metabolic end-product(s) of the oxygen system is which of the following?
A.
Carbon dioxide and water
B.
Lactic acid
C.
Heat
D.
All of the above

The metabolic end-product(s) of the oxygen system is Carbon dioxide and Water

Explanation:

Our body creates energy via combustion of carbohydrates , ammino acid and fats in presence of oxygen, this is called as aerobic metabolism.Oxygen system  in aerobic metabolism oxidizes carbohydrates and provide free oxygen atom . These oxygen atom gets attached to carbon in the carbon dioxide molecule, which is excreted. By products of such aerobic metabolism are carbon dioxide and water.

The answer is 4f======since electrostatic force is given by    we let f be the electrostatic force when  r = 1 m    if we let  denote the electrostatic force when the distance is decreased so that r = 0.5m, then    we established earlier that f = kq₁q₂. therefore    the force will now be 4f.