18. Suppose you add 45 J of heat to a system, let it do 10 J of expansion work, then returns the system to its initial state by cooling and compression. Which statement is true for this process? (A)\(\Delta H ＜ \Delta E\) (B)The work done in compressing the system must exactly equal the work done by the system in the expansion step. (C)\(\Delta H = 70\) J (D)The change in the internal energy for this process is zero. (E)none of the above