物理--选修3-3一氧气瓶的容积为0.08m³，开始时瓶中氧气的压强为20个大气压．某实验室每天消耗1个大气压的氧气0.36m³．当氧气瓶中的压强降低到2个大气压时，需重新充气．若氧气的温度保持不变，求这瓶氧气重新充气前可供该实验室使用多少天．

用力推放在水平地面上的木箱，没有推动（图1），则推力____ （大于/小于/等于）木箱受到的摩擦力；用手握起瓶子时（图2），瓶子受到的重力与____ 力是一对平衡力．

补全对话(选择)。

A: Hello. Zhang Yu! ____

B: I'm reading a newspaper.

A: ____

B: Yes. There is a report about Zhou Yang.

A: ____

B: She is a player in China female short track speed skating team. ____

A: When and where was she born?

B: ____

A: Do you want to be a famous person like her when you grow up?

B: Aha, of course. So I have to work hard at school.

A: Well. You're a good student.

B: Thank you!

A. Who is Zhou Yang?

B. What's your hobby?

C. She was born in Jilin Province on June 9^th, 1991.

D. What are you doing now?

E. She won the gold medal in the 2014 Winter Olympic Games in Sochi.

F. How do we succeed in life? Is she from China?

G. Is there anything new on it?

高尔基曾经说过“要爱惜自己的青春！世界上没有再比青春更美好的了，没有再比青春更珍贵的了”。那么青春更体现在一个人（   ）   

有学者指出：事实上农民远非如许多人想象的那样是一个制度的被动接受者，他们有着自己的期望、思想和要求。他们一直有着“反道而行”的“对应”行为，从而以不易察觉的方式改变、修正，或是消解着上级的政策与制度。下列史实中，最能佐证材料观点的是(  )