题目内容

如果两个同维的向量组等价, 则这两个向量组()

A. 相等
B. 所含向量的个数相等
C. 不相等
D. 秩相等

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根据三力平衡汇交定理，下面说法正确的是（）。

A. 共面不平行的三个力互相平衡必汇交于一点
B. 共面三力若平衡，必汇交于一点
C. 三力汇交于一点，则这三个力必互相平衡
D. 共面三力中若两力汇交于一点，则第三个力必通过这一点

关于力在某轴上的投影和力在某轴方向上的分力的说法，正确的是（）。

A. 两者都是矢量
B. 两者都是代数量
C. 投影为代数量，分力为矢量
D. 分力为代数量，投影为矢量

力可以沿着作用线移动而不改变它对刚体的运动效应。

A. 对
B. 错

Directions：You will hear a long conversation three times, and fill the blanks with the words you'll have heard from the conversation. For blank 1, 2, 4, 5, 6 and 9, you'll fill in with the exact word, while the rest with a sentence.[音频]ConversationM:And you know, one thing that I want to ask you. It's great that you have had this experience of teaching in Indonesia and following up on what you just mentioned. What would you 1. ___ for students who do not live in an 2. _ country and, you know, they want to learn. I don’t know about perfecting but they want at least to be able to communicate decently. How can they go about this?W: Yeah, it's really hard. That's the real struggle because, 3.__________________________________, but I really don't 4. _ much with Dutch people and my boyfriend's English is so good that we just basically speak English all the time. So I have to make a real effort to practice. There is as much listening 5. _ as I want --- all I have to do is turn on the TV.M:And reading also, right?W: Yeah, reading. There is plenty I can get to read and listen to, but for speaking, there really is no 6. _ for trying to speak and use the language in a relaxed atmosphere. 7.. And for that gosh, 8. ____. In Sweden, they have a really cool system called Study Circles. Well, it's not... it's like a course. But really, you just have a 9. _ leader who is there, sort of, as a coaching guide and to help out, 10. _________________________________________.