题干

关于电流和电阻,下列说法中正确的是(   )

A:电流的方向与导体中正电荷的定向移动方向相同

B:金属导体温度降低时,由于自由电子的热运动减慢,所以电流减小

C:对给定的导体,由R=U可知,通过导体的电流I越大,导体的电阻R越小

D:两个定值电阻连接后的总电阻一定比其中某个电阻的阻值大

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A

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    When Steve Jobs was born on Febuary24,1955, in San Francisco , California, his unmarried mother decided to put him for adoption because she wanted a girl. So in the middle of the night, his mother called a lawyer named Paul Jobs and said, “We have an unexpected baby boy; do you want him?” But his mother told his future parents to promise that they would send Jobs to college. After Steve Jobs graduated from high school, he went to college but decided to drop out because it was so expensive that he had to sleep on the floor in his friends' rooms.

    At 20, he and a friend(Steve Wozniak) started a company in a garage on April 1, 1976. Jobs named their company ----Apple in memory of a happy summer he had spent as an orchard (果园) in Oregon.

    After 10 years of hard time and failures, starting from two kids working in a garage, Apple computer eventually grew into a big company with over 4000 employees.

    At 30, Jobs , however, was fired from the company he co-founded. But after he had to leave the company, Apple was under heavy pressure from rival (对手) Microsoft and in 1996 posted billions of dollars in losses. Apple needed Steve Jobs and he was appointed as Apple' CEO in1997. Under his leadership, Apple returned to profitability and introduced new products such as the iPhone and the iPod.

    Steve Jobs once said, “Sometimes life hits you in the head with a brick, Don't lose faith. I'm convinced that the only thing that kept me going was that I loved what I did. You've got to find what you love. If you haven't found it yet, keep looking.