燃烧太晚所形成的畸形示功图特征之一是（）。
A.爆发压力降低
B.膨胀线降低
C.压缩压力降低
D.排气温度降低
参考答案：A
-----His letter arrived a month ago. ______ to Peter?
----- Yes. You know, I have been busy in preparing for the final exam all the time. [ ]
A. Didn’t you write
B. Don’t you write
C. Hadn’t you written
D. Haven’t you written
已知全集U=R，集合A={x|3≤x＜7}，B={x|x2-7x+10＜0}，则CR(A∩B)=[ ]
A.(-∞，3)∪(5，+∞)
B.(-∞，3)∪[5，+∞)
C.(-∞，3]∪[5，+∞)
D.(-∞，3]∪(5，+∞)
