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【简答题】
2-12 试计算工作在 1200nm 到 1400nm 之间以及工作在 1400nm 到 1600nm 之间的光波的频带宽度。假定光在光纤中的传播速率为 2*10e8m/s.
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皮皮学刷刷变学霸
举一反三
【单选题】----They go to school early in the morning． ---_________________．
A.
So do Tom．
B.
So Tom do．
C.
So does Tom．
D.
So Tom does．
【多选题】水平角的观测方法有测回法和方向法,其观测的限差有所不同,方向观测法的限差有( )。
A.
半测回归零差
B.
半测回较差
C.
一测绘2C互差
D.
同方向各测回互差
E.
一个测回差
【单选题】听力原文：M: Tom was late for his job this morning. W: It's nothing new for him. Q: What does the man metal? (2)
A.
Tom is always late for his job.
B.
Tom is a new employee.
C.
Tom had nothing to do this morning.
D.
Tom went to bed late last night.
【简答题】课本页,项目三实训二业务一中第三题,生产领用原材料的材料单价如何查找?(可用软件操作拍照形式上传答案,也可文字叙述)。
【单选题】Tom does morning exercises every day. (改为否定句) Tom morning exercises every day.
A.
doesn’t do
B.
don’t does
【单选题】---Has Tom finished his homework? ---I don’t know. But he _________ it the whole morning.
A.
did
B.
does
C.
was doing
D.
is doing
【简答题】填空。 1. Tom never gets up late, _____ _____ ? (完成反意疑问句) 2. He does morning exercise every day. (变成否定句) He _____ _____ morning exercise every day.
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