The Figure Shows a Schematic of Joule's Classic Experiment, in Which

The figure shows a schematic of Joule's classic experiment, in which weights are dropped a certain distance. As the weights drop, they turn a paddle immersed in water. The experiment proves that

A) mechanical energy can be transformed into heat.
B) 1 cal of heat equals 4.184 J.
C) work and heat cannot be separated.
D) in order to change the temperature of the water you have to do work on it.
E) (A) and (B)