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问题 选择题

不能在真空中传播的“波”是（　　）

A．声波

B．光波

C．电磁波

D．无线电波

答案

无线电波、光波、电磁波都可以在真空中传播；声波不能在真空中传播，它传播时需要靠介质；

故选A．

改错题

The village was always very quiet.The people lived there.  小题1:          

were busy working in their fields during the day ,and           小题2:           

went to bed early at night,tiring after a long day’s hard          小题3:           

work.All of them had lived in a village for all their            小题4:            

life and have never left for more than one day at a time.         小题5:           

On these days they left,they got up early in the morning.        小题6:           

They filled their carts with fruit and vegetables and sheeps,        小题7:           

and went on the market in the town beyond their valley.           小题8:           

They came back in the evening and with some money and perhaps a 小题9:            

present for their children.That was their left-hard yet            小题10:          

simple,but not unhappy.
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单项选择题

下列肿瘤的诊断中，不正确的是

A．超声波对肿瘤部位、性质及范围诊断有一定参考价值

B．放射性核素检查可显示出各种大小的肿瘤

C．X线检查对肿瘤诊断有帮助

D．免疫学检查对早期肿瘤诊断有价值

E．同工酶与CEA同时测定可提高癌的诊断价值
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