Rubbing your hands against each other can make them hot. The faster you rub, the hotter they are. Which of the following statements is/are correct?

(1)the molecules of the hands have zero total kinetic energy because they vibrate about fixed positions.
(2)the work done against friction between the hands is converted into the internal energy of the hands.
(3)the temperature of the hands is directly proporti9nal to the kinetic energy of the hands.