下列有机物的命名中,正确的是 [ ]
A. (2-乙基戊烷)
B. (3-甲基-2-戊烯)
C. (2-甲基-3-戊炔)
D. (1-甲基-5-乙基苯)
答案:B
The journey around the world took the old sailor nine months, ________ the sailing time was 226 days.[ ]
A. of which
B. during which
C. from which time
D. for which
寄存器R15用作()。
A.栈指针寄存器
B.程序计数器
C.当前程序状态寄存器
D.基地址寄存器