試題詳解

45. The figure shows a closed cycle for a gas. From c to b, 60 J is transferred from the gas as heat. From b to a, 100 J is transferred from the gas as heat, and the magnitude of the work done by the gas is 80 J. From a to c, 400 J is transferred to the gas as heat. What is the work done by the gas from a to c?

(A) -240 J
(B) 240 J
(C) 320 J
(D) -320J
(E) -160 J