13. One mole of an ideal gas (Cv = 20 J•K-1 •mol-1 ), initially at 1.0 atm and 300 K, absorbs 100 J of heat and performs 500 J of work in a certain process. What is the final temperature (in K) of the gas?
(A) 280
(B) 290
(C) 300
(D) 320
答案：A
統計：A:1,B:0,C:0,D:0,E:0
難度：計算中