When an object is raised vertically, work is done against . What one word completes the sentence? please help quickly!!

The transfer of heat through the movement of a gas or liquid a. convection b. conduction c. radiation

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.

It is really hard for me right know