问题
名词解释
经线
答案
参考答案：
所有通过地轴的平面，都和地球表面相交而成为圆，这就是经线圈。每个经线圈都包含两条相差180°的经线，一条经线则只是一个半圆弧。所有经线都在两极交会，所以经线都是呈南北方向，长度也彼此相等。
搜题请搜索小程序“爱下问搜题”
经线
参考答案：
所有通过地轴的平面，都和地球表面相交而成为圆，这就是经线圈。每个经线圈都包含两条相差180°的经线，一条经线则只是一个半圆弧。所有经线都在两极交会，所以经线都是呈南北方向，长度也彼此相等。
小明家中有小小实验室，他收集的物质有①溶液：HCl、AgNO3、Ba（OH）2和H2SO4；②固体：NaCl、CaCO3、CuO和Na2CO3．小明按如图所示的方法实验，有气泡产生，一会儿蜡烛熄灭，白色固体消失．看到上述现象后，小明的同学小亮认为试剂瓶中的溶液为盐酸，玻璃杯中的固体为碳酸钙．除此之外，你认为溶液和固体的组合还可能是什么？请填入表中（任写三种不同组合）．
| 组合种类 | 1 | 2 | 3 |
| 溶 液 | ______ | ______ | ______ |
| 固 体 | ______ | ______ | ______ |
| 完形填空 | ||||
| I ran across an old photo of him the other day, thinking of some old things. He's been dead for 25 years. His name was Rex. 1 was his favorite recreation(娱乐). He had so much 2 in the water as any person I have known. You didn't have to throw a stick in the water to 3 him to go in. Of course, he would bring back a stick to you if you 4 throw one in. That 5 me of that night, 6 he brought back a small box that he found somewhere- how 7 nobody ever knew. Since it was Rex, it 8 easily have been half a race. The box wasn't a good one. It was just a 9 old piece that somebody 10 . Still it was something he wanted, probably 11 there was some difficulty in transportation(运输). And that he thought could test his courage. We first knew about his achievement when, deep in the night, we 12 him trying to get the box up onto the porch(门 厅). It sounded 13 two or three people were trying to tear the house 14 . We came downstairs and turned on the 15 light. Rex was on the top step trying to pull the thing up, but it had 16 somehow. And he was just holding his own(坚持着). I suppose he would have held his own 17 dawn if we hadn't helped him. The next day we carried the box miles away and threw it out. If we had thrown it out in a 18 place, he would have brought it home again, as a small token(象征)of his strength in such matters. 19 , he had been taught to carry heavy wooden objects about and he was 20 of his skill. | ||||
|