what is the answer to the question "Two boys of equal mass go up to the first floor of a building. Boy A takes the stairs, boy B takes the elevator. Which boy will have more potential energy when they reach the first floor"

What accounts for an increase in the temperature of a gas that is kept at constant volume? a. energy has been removed as heat from the gas. b. energy has been added as heat to the gas. c. energy has been removed as work done by the gas. d. energy has been added as work done by the gas.