An Ideal Gas at STP Is First Compressed Until Its

Multiple Choice

An ideal gas at STP is first compressed until its volume is half the initial volume, and then it is allowed to expand until its pressure is half the initial pressure. All of this is done while holding the temperature constant. If the initial internal energy of the gas is U, the final internal energy of the gas will be

A) U.
B) 2U.
C) U/2.
D) U/3.
E) U/4.