问题
单项选择题
DME地面台的识别码为莫尔斯编码，识别频率为（）
A.1000Hz
B.1100Hz
C.1300Hz
D.1350Hz
答案
参考答案：D
搜题请搜索小程序“爱下问搜题”
DME地面台的识别码为莫尔斯编码，识别频率为（）
A.1000Hz
B.1100Hz
C.1300Hz
D.1350Hz
参考答案：D
| 完型填空。 | ||||
| Mary was born in a worker's family. But she always 1 her friends that her father is very rich. They know her very well, but 2 says anything about it. Last month Miss Brown, 3 friends, asked Mary to her birthday party. The girl went there with some 4 . She got on a bus but there were a lot of people in it. She couldn't find any seat. A young man saw this, he 5 and said, "Take my seat, please." Mary 6 him and sat down. To her surprise, she saw him again at the party. She was very 7 and went to say hello to him. They began to dance. The young man heard a piece of 8 and liked it very much. He told the girl he taught piano at school. "I bought a piano ten years 9 ," said Mary. "You must play it well, I think." " 10 , I can't. I don't know how to get the lid (盖子) open," answered the girl. | ||||
|