What is the main reason why would a fan be expected to warm the air that passes through it? A or B? A. The fan does work on the air in the room leading to an increase in its thermal energy and temperature.
B. The fan transfers heat to the air in the room leading to an increase in its thermal energy and temperature.

A. The fan does work on the air in the room leading to an increase in its thermal energy and temperature.

Explanation:

Fans move fluid, typically a gas, such as air, through a room or an enclosure. A fan consists of a rotating arrangement of vanes or blades (impeller), which acts on the air. The action of the impeller does work on the fan by compressing and moving the air forward, doing work on it in the process. The work done on the fan leads to an increase in the thermal energy of the air.

what is the speed of a softball that travels 20m in 2secs

speed = 20/2 = 10 m/s