问题
填空题
自由空间中电波传播损耗和工作频率f有关,当频率f增大一倍时,损耗将增加()。
答案
参考答案:6dB
自由空间中电波传播损耗和工作频率f有关,当频率f增大一倍时,损耗将增加()。
参考答案:6dB
Trudy’s class has a newspaper. The students write stories, articles and poems for it. Then one of them types their work into a computer and prints it out. The teacher puts up everything on the wall so that it looks like a large, open newspaper. One day Trudy said to the teacher, “most newspapers have advertisements. Can we have our advertisements? The teacher thought this was a good idea. She made Trudy the advertising manager and Trudy asked the other students to advertise in the newspaper. Here are some of the advertisements she received.
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