题干

如图所示电路中,电源电压不变,R1为定值电阻,R2为滑动变阻器.闭合开关S,当滑动变阻器滑片P向左移动时,下列判断正确的是(   )

A:电压表示数变大,电流表示数变大

B:电压表示数变小,电流表示数变小

C:电压表示数变大,电流表示数变小

D:电压表和电流表的示数的比值不变

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A,D

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    Humans love to observe animals, and modern-day zoos and wildlife preserves help meet that interest while providing facilities to assist with conservation programs. Zoology careers in zoos can range from overseeing breeding programs, to creating the proper diet for a deer, to cleaning the tiger's cage. Many volunteer and entry-level jobs are available for people that love animals.