One day， a Chinese student goes to study English in England. His family name is Sun. It is the1as the word "sun."

    England is a country with2It is often cloudy or misty(多雾的)，and it3again， so the days there4get much sunshine(阳光) all the year.

    When the Chinese student gets to London，a tall 5policeman with a long face 6his passport(护照) to check(检查) it. The policeman finds the Chinese name "sun" in the passport. He 7it is pronounced(发音) just like the 8word "sun". So he says to the Chinese student， "I see your name is Sun， you're wanted here. You bring sunshine9England， so we don't want you to10." They smile.

如图所示，有一半圆弧光滑轨道，半径为R，在与圆心等高的位置静止放置一个带正电的小球A，其质量为m，MN之间有一方向水平向左的匀强电场，让小球A自由滚下进入匀强电场区域，水平面也是光滑的，下列说法正确的是（   ）

右图是一个水龙头打开后出水情况的统计图。这个水龙头打开的时间和出水量成____比例关系，照这样计算，出15升的水需要____秒。