化学使世界变得绚丽多彩，如图是铜与其他物质之间的转化关系

完形填空。

    A boy and a girl catch a bird and 1 it in a birdcage (鸟笼）. They like it 2 and 3 it every day. A cat sees the bird and wants 4 her supper. 5 the bird is in the cage. She can't catch it. So she is very 6.

    One day, she opens the door of the cage 7 wants to catch it. But the bird flies away. The cat 8, and she has 9. The two children 10 and　see the bird isn't in. They are very angry and put the cat into the cage.

如图是小浩同学8月1日〜7日毎天的自主学习时间统计图，则小浩同学一天中自主学习时间最长是____ 小时，这七天平均每天的自主学习时间是____ 小时．

已知直线$l\left\{\begin{array}{c}x=5+\frac{\sqrt{3}}{2}t\\ y=\sqrt{3}+\frac{1}{2}t\end{array}\right.$（$t$为参数），一坐标原点为极点，$x$轴的正半轴为极轴建立极坐标系，曲线$C$的极坐标方程为$\rho =2\cos \theta$

为了缓解民众“看病贵”的问题，我国对基本药物实行政府限价，但由于企业利润得不到保障，一些低价药屡屡“玩失踪”，导致部分群众购药需求难以得到满足。为了解决低价药物的供给问题，需要政府（   ）。

①按照价值规律的要求进行宏观调控          

②明确规定企业负有保障低价药物供应的责任

③加大对生产低价药物企业经营管理干预的力度

④以税收优惠等政策对生产低价药物企业提供支持