上海—120.6135发动机喷油提前角在上止点前（）mm。
A、10～15
B、15～20
C、20～25
D、28～31
参考答案：D
— Did you get a ticket?
— No, I_______, but there wasn't any left.
[ ]
A. had to
B. attempted to
C. decided to
D. managed to
(1)建立项目文件，文件名为“xm”。
