问题
单项选择题
下列安全防护措施中，对射线防护无效的是( )。
A．时间防护
B．光照防护
C．屏蔽防护
D．距离防护
答案
参考答案：B
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下列安全防护措施中，对射线防护无效的是( )。
A．时间防护
B．光照防护
C．屏蔽防护
D．距离防护
参考答案：B
| 阅读理解 |
| Mike wants to borrow an eraser from his friend Ann.But Ann's eraser is at home.Mike wants to buy one in the shop.The shop near the school sells books,pens and many things like that.The shop is big and nice.It is open from Monday to Saturday.It opens at 8:00 in the morning and closes at 6:00 in the evening |
| 1. Mike wants to borrow . |
| A. books B. a pen C. a ruler D. an eraser |
| 2. Ann's eraser is . |
| A. at home B. at school C. in her bag D. on the desk |
| 3. The shop near the school sells . |
| A. food B. fruit C. drink D. school things |
| 4. The shop opens . |
A. at 6:00  B. at 8:00 C. in the morning D. in the evening |
| 5. The shop is . |
| A. big B. nice C. nice but small D. big and nice |