Beckham in a Football Movie

    Do you like football? You must know David Beckham. But do you know that he will be in a movie? He will be David Beckham in the movie Goal.

    Beckham said, "I want to teach kids how to play football when I finally hang up my boots." "I believe that Goal will send a positive message to kids around the world."

    Beckham, 29, said, "I think that Goal will make football more popular in America and Asia. I am very happy because I can help do it," he said.

学习了电流、电压和电阻知识后，同学们发现电流与水管中的水流相似，电压与水压差相似，李明和同学们提出，导体对电流的阻碍作用可能与水管对水流阻碍作用相似，所以影响导体电阻大小的因素，他们提出了以下猜想：

猜想一：（类比管道长短）导体电阻的大可能与导体的长度有关；

猜想二：（类比管道精细）导体电阻的大小可能与导体的横截面积有关．

于是他们从实验室老师那儿借来了某合金材料制成的各种长度和横截面积的电阻丝，并设计了如图所示的电路．

1943年2月，罗斯福在致斯大林的一封贺信中说：“是你们制止了侵略浪潮，成为盟军反侵略战争的转折点。”这一“转折点”是指