光纤通信的短波长传输窗口是()μm。
A.0.65
B.0.85
C.1.31
参考答案:B
Kate often goes to work _____ breakfast. It's bad for her health. [ ]
A. with
B. without
C. on
D. not have
胶件有无骨架,尺寸变化规律()。
A.缩小
B.不变
C.视具体结构而定
D.以上都不是