A sign can be found in the front yard of a house in the US. The people living here want to let their dog play outside and ensure it won’t run into the street. So, they hire a company to set up an
For almost two months Dominic York, a 23-year-old hairdresser, wandered about hospitals all night, wearing a white coat and pretending he was a doctor. Yesterday he proudly claimed in court that despi
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rad/s=1 rad/s
可知：
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s=2π s.