问题
选择题
用下列机械，使重量同为G的物体都处于静止，用力最大的是（均不计摩擦）[ ]
A．
B．
C．
D．
答案
答案：B
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用下列机械，使重量同为G的物体都处于静止，用力最大的是（均不计摩擦）[ ]
A．
B．
C．
D．
答案：B
| 阅读理解。 | ||
to send their signals to faraway places. This was because most cities had only one antenna tower for mobile phones. Today's mobile phones are small and easy to use. Now most cities have a lot of antenna towers, not just one. This means that each mobile phone doesn't have to send its signal far away, so they don't need to be so powerful. Mobile phones today use small batteries. A large city, where lots of mobile phones are used, can have hundreds of towers. Do you know what use a mobile phone has? Yes, you can use it to do a lot of things. Call your friends and family from almost anywhere. Call the police immediately if there is an accident in the street. Send or receive messages. Sending short written messages is a popular way to use your mobile phone. Many people use short forms of words, so the messages are quick to write and read. Can you guess what these messages mean? Try reading them out. What do you hear? RUOK? CUL8r! That's EZ! Will I C U B4 2moro? That's Gr8! | ||
| 1. The writer talks about _____ uses of a mobile phone. | ||
| A. three B. five C. seven D. nine | ||
| 2. Why did the mobile phones need large powerful batteries some years ago? | ||
| A. Because most cities had only one antenna tower. B. Because the mobile phones were too large. C. Because the mobile phones could be used for a long time. D. Because the mobile phones had to send their signal to far-away places. | ||
| 3. What does the writer think of today's mobile phones? | ||
| A. They are small but very powerful. B. They are very popular and cheap. C. They are very easy for us to use. D. They are big enough to send a signal. | ||
| 4. What does "Will I C U B4 2moro?" probably mean? | ||
| A. Will I see you before two past four in the morning? B. Will I see you by 4:02 in the morning? C. Will I see you before tomorrow? D. Will I see you by four tomorrow? | ||
| 5. What does the writer write the article (文章) for? | ||
| A. To give us some common knowledge of the mobile phone. B. To introduce how the mobile phone works and what use it has. C. To tell us what short forms of words mean in written messages. D. To show us in what way the mobile phone is expected to develop. |
