人眼对可见光谱的分辨能力在()处最灵敏。
A.420nm
B.540nm
C.700nm
参考答案:B
—Who in Tom's family will come to your birthday party?
—Either Tom ______ any of his sisters is coming. [ ]
A. and
B. but
C. or
D. nor
发动机装配过程中,控制的最关键的要素是()
A、螺栓力矩
B、装配顺序
C、清洁度