决定熟料中硅酸盐矿物含量的是()。
A、LSF
B、KH
C、SM
D、IM
参考答案:C
— Look at that model ship.
— I know, but it looks like a real one. It's just ______. [ ]
A. small
B. very small
C. smaller
D. smallest
晶闸管的控制角是60o,其导通角是()。
A、0o
B、60o
C、120o
D、180o