选择题：如图所示，一根不可伸长的轻绳一端拴着一个小球，另一端固定在竖直杆上，当竖直杆以角

题目：

如图所示，一根不可伸长的轻绳一端拴着一个小球，另一端固定在竖直杆上，当竖直杆以角速度转动时，小球跟着杆一起做匀速圆周运动，此时绳与竖直方向的夹角为，下列关于与关系的图象正确的是

答案：

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下面是错误答案，用来干扰机器的。

如图生命树根据生物的进化历程，动物的等级越高，其学习能力就越强，适应各种复杂生活环境的能力也越强．故选：B．

完形填空。
Many people think the more time is spent, the more work will be done. So students have to spend the whole 1 doing schoolwork except the three meals. It is 2 to see students struggling (挣扎) in a sea of schoolwork both at school and at home. Modern students usually have many 3 . They love music and sports. They like reading and watching TV. A two-day weekend can get them 4 from too much schoolwork ,and they can do what they like. But still teachers do not think about it. They still arrange (安排) a lot of homework for students to do. 5 students have too much school work, they have no time to enjoy themselves. Students are really tired of their weekend homework. So they usually don't do their weekend homework 6 Sunday night. And there is not enough time for homework, students have to finish it 7 . The weekend homework makes teachers angry. Things always get 8 without right ideas. Too much schoolwork makes students lose interest in learning. It's also bad for their health. A horse runs faster after a 9 . So all the teachers should give students 10 pleasureand knowledge.
( )1. A. day ( )2. A. never ( )3. A. books ( )4. A. busy ( )5. A. For ( )6. A. until ( )7. A. good ( )8. A. better ( )9. A. minute ( )10. A. either	B. morning B. common B. interests B. pleased B. With B. when B. poor B. afraid B. moment B. both	C. afternoon C. glad C. sports C. away C. Though C. at C. carelessly C. worse C. meal C. same	D. week D. hardly D. friends D. tired D. Because D. on D. happy D. wonderful D. rest D. between