坐标系统是由坐标原点位置、坐标轴指向和尺度所定义的。在GPS定位中，坐标系原一般取（

2010年10月15日至18日召开了中共十七届五中全会。加快转变经济发展方式是这次会议上的热门话题，之所以要倡导转变经济发展方式，是因为

①物质决定意识，意识反作用于物质        ②实践是主观见之于客观的活动

③个人和社会是统一的                                    ④价值观影响着人们改造世界的活动

A．①②③

B．②③④

C．②④

D．①③④

简述朗肯理论适用条件？

填入适当的词。

1. I haven't heard from him_______ he went to America.

2.He won't be here_______ he is invited.

3. He will not go to the cinema______ he is very busy.

4. We found the key_______ she had left it.

5. We found the books two days ______he had gone away.

6. We had no sooner got to the station ________the train left.

7. He speaks English ______ he were an Englishman.

8.He is explaining clearly______  they can understand.

9. Do not leave the room______ you have finished the test.

10. She sang______ she went along.

三角皮带的剖面积越大，传递的功率就（）。

A.越大

B.越小

C.不变

D.变化不大