重新排列以下各句，用正确的大小写形式写出合乎逻辑顺序的短文．

1．How far do you think the sun is away from us?

2．You may hardly believe that it will take 1,300,000 glow(热量) to fill(填满) it.

3．And how long does it take to get there?

4．If the sun is cold, we must all be dead(死亡).

5．If you heard this before, you would know that the sun can give out a great amount of light and heat.

6．If you take a train, travelling at the speed of 60m/h without stopping, it will take more than one hundred and seventy years to reach the sun.

7．And when you arrive there, how large do you think the sun is?

8．And if the rays(光线) fall on us, we all have to be burned up(烧死).

9．But only 1/2,000,000,000 of the warmth(热量) can reach the earth.

10．The reason why that we're safe(安全) is because there is some air which cuts off(削弱) part of the sun's great heat.

质量为M的人站在地面上，用绳通过定滑轮将质量为m的重物从高处放下，如右图所示，若重物以加速度a向下降落(a<g)，则人对地面的压力大小为(　　)

A．(m＋M)g－ma	B．M(g－a)－ma
C．(M－m)g＋ma	D．Mg－ma

GDP是衡量一个国家或地区经济规模、综合国力和国民收入水平的重要指标。它是分析和判断宏观经济运行状况、正确实施宏观调控政策的重要依据，但它的局限性在于难以反映经济与社会发展的协调性。这反映了：①矛盾有主要和次要方面 ②事物都是一分为二的③矛盾有主要矛盾和次要矛盾之分 ④事物都是表里如一

A．①③

B．②④

C．①②

D．③④

GDP是衡量一个国家或地区经济规模、综合国力和国民收入水平的重要指标。它是分析和判断宏观经济运行状况、正确实施宏观调控政策的重要依据，但它的局限性在于难以反映经济与社会发展的协调性。这反映了：①矛盾有主要和次要方面 ②事物都是一分为二的③矛盾有主要矛盾和次要矛盾之分 ④事物都是表里如一

A．①③

B．②④

C．①②

D．③④

下列表示重量单位的是______.

A. AM        B. PRC        C. kg        D.NBA