问题 选择题

俗话说“霜前冷,雪后寒”,这句话运用物理学知识解释,下列说法正确的是(  )

A.霜形成之前的气温一定比下雪后的气温低

B.霜形成之前的气温比雪形成后的气温高

C.霜是地面形成的,气温必须在0℃以下,雪在高空形成,雪后熔化需要吸收大量热量,使地面气温降低

D.以上说法都不对

答案

AB、“霜前冷,雪后寒”,霜前冷是针对下霜前后相比,霜后冷;雪后寒是针对下雪前后相比.不是霜前和雪后进行比较.故AB选项都错误.

C、霜是地面的空气中水蒸气在低温下凝华而形成的冰晶,水蒸气要发生凝华,水蒸气温度要足够低,所以霜前冷;雪是水蒸气凝华形成的,凝华放热,所以空气温度不是很低,雪后积雪熔化,熔化吸收热量,使空气温度较低,所以雪后寒.故C选项正确.

D、C选项正确,所以D选项错误.

故选C.

阅读理解

阅读理解

                                                                     Warren Buffett

     For someone who is such a successful investor, Warren Buffett comes off as a pretty ordinary guy.

He was born on August 30, 1930.   1     He used to go door-to-door and sell soda water. When his

family moved to Washington, Buffett became a paperboy for The Washington Post. Buffett ran his five

paper routes and even added magazines to round out his product offerings. While still in school, he was

making $175 a month, a full-time wage for many men.

        2     He spent $1,200 on 40 acres of farmland in Nebraska. He and a friend also made $50 a

week by placing pinball machines in barber shops. They called their venture(企业)Wilson Coin

Operated Machine Co.

     Although already a successful small-time businessman, Buffett wasn’t interested in going to college

but ended up at the University of Pennsylvania ---- his father encouraged him to go.  3    . But he

was turned down and that had to be one of the worst admission decisions in Harvard history. The

outcome affected Buffett’s life, for he ended up attending Columbia Business School, where he studied

under Professor Benjamin Graham, the father of securities analysis who provided the foundation for

Buffett’s investment strategy.

     From the beginning, Buffett made his fortune from investing. He started with all the money he had made from selling soda water, delivering papers, and operating pinball machines. Between 1950 and 1956, he grew his $9,800 to $14,000.   4    And then he gradually drew in other investors through word of mouth and very attractive terms.

      5     He doesn’t collect houses or cars or works of art, and he disdains(鄙视)companies that waste money on expensive cars, private dining rooms, and high-priced real villas. He is a creature of habit-----same house, same office, same city and same soda water.

A.Then Bufftt applied to Harvard Business School.

B.Buffett is more likely to be found in a four star restaurant.

C.When he was 14, Buffett kept great interest in investment.

D.Even as a young child, Buffett was serious about making money.

E.One thing is for sure about Buffett: he is happy doing what he is doing.

F.Buffett’s investment strategy mirrors his lifestyle and his overall philosophy.

G.From there, he organized investment partnerships with his family and friends.

单项选择题