一台六缸二冲程柴油机的发头间隔角是()。
A.60
B.180
C.120
D.360
参考答案:A
____you are familiar with the author’s ideas, try reading all the sections as quickly as you possibly can.
A.Now that
B.Ever since
C.So that
D.As long as
阴偏哀、阳偏衰的概念及成因如何?