Exothermich cools and endo heats so it heats
The lungs hold air that is taken in. Oxygen gas noticeable all around moves into the blood. The heart pumps to transports this oxygenated blood to cells in the body that need it to deliver vitality.
All three have the same current, so that is not a factor. Wattage (power) is E*I or i^2 R. The higher the resistance, the more power dissipated. The answer is R3 because it has the highest resistance.
R3 <<<< ===== answer.
A light meter, because illu is a root for light
