【解析】

小红同学对探究分子性质的实验（图1）进行了改进．如图2所示，试管丁、戊中各有一张每隔2厘米滴有一滴酚酞溶液的滤纸条，试管戊中装有适量浓氨水的小药瓶固定在橡皮塞上，小药瓶上无瓶塞．关于实验有以下说法，其中说法正确的是（    ）

①图2比图1的实验更环保、更节约；

②图1和图2的实验均能证明分子在不断的运动；

③浓盐酸有挥发性，仅将浓氨水换成浓盐酸也可达到实验目的；

④若将戊浸入冰水中，滤纸条不会变红．

① What will your dad do next week? ____     A. He is a doctor.

② Why do you like summer? ____     B. It is green.

③ What does he do? ____     C. I can see thirteen.

④ Did you have a good time? ____     D. Because I can swim.

⑤ When did you come home?____     E. We’re going to visit the art museum.

⑥ What colour is it?  ____     F. Yes, I enjoyed myself very much.

⑦ What are you going to do tomorrow? ____     G. I did my homework.

⑧ How many cows can you see?  ____     H. At about eleven in the evening.

⑨ What’s Mary doing now?  ____     I. She’s sleeping in bed. She’s ill.

⑩ What did you do last night?   ____     J. He’ll go fishing.

如图所示，将一劲度系数为k的轻弹簧一端固定在内壁光滑，质量为M，半径为R的半球形容器底部O′处（O为球心），另一端与质量为m的小球相连，小球静止与P点．已知容器与水平面间的动摩擦因数为μ，OP与水平方向间的夹角为θ=30°，则半球形容器对地面的压力大小为____，弹簧对小球的弹力大小为____．

（2016•天津）地租是城市各种环境因素在经济上的综合表现，图4显示了某市中心城区地租从中心向边缘递减的变化趋势，由于环境质量、基础设施等因素的不同，城市不同方向的地租变化程度存在差异。该市规划子在甲地建设产业园区，最适宜的是