You are rapidly pumping air into a tire with a bicycle pump. At the same time, helium gas is rapidly escaping out of a balloon. Which of the following statements is true?
(a) The pump cools down while the helium gas warms up as it is expelled.
(b) The pump warms up while the helium gas cools down as it is expelled.
(c) The pump cools down while the helium gas also cools down as it is expelled.
(d) The pump warms up while the helium gas also warms up as it is expelled.