题干

如图的电路中,灯L1标有“6V、0.5A”的字样,灯L2标有“3V、0.3A”的字样.该电路长时间工作时只允许灯____正常发光,且此时的电源电压是____V.

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L2,6.6

同类题1

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                                                                                             Three Boys and a Dad
      Brad closed the door slowly as Sue left home to visit her mother. Expecting a whole day to relax, he was thinking whether to read the newspaper or watch his favourite TV talk show on his first day off in months. “This will be like a walk in the park.” he'd told his wife. “I'll look after the kids, and you can go visit your mom.”

    Things started well, but just after eight o'clock, his three little “good kids”---Mike, Randy, and Alex --- came down the stairs in their night clothes and shouted “breakfast, daddy.” When food had not appeared on within thirty seconds, Randy began using his spoon on Alex's head as if it were a drum. Alex started to shout loudly in time to the beat(节拍) . Mike chanted “Where's my toast, where's my toast” in the background. Brad realized his newspaper would have to wait for a few seconds.

    Life became worse after breakfast. Mike wore Randy's underwear on his head. Randy locked himself in the bathroom, while Alex shouted again because he was going to wet his pants. Nobody could find clean socks, although they were before their eyes. Someone named “Not me” had spilled a whole glass of orange juice into the basket of clean clothes. Brad knew the talk show had already started.

    By ten o'clock, things were out of control. Alex was wondering why the fish in the fish bowl refused his bread and butter. Mike was trying to show off his talent by decorating kitchen wall with his color pencils. Randy, thankfully, appeared to be reading quietly in the sitting room, but closer examination showed that he was eating apple jam straight from the bottle with his hands. Brad realized that the talk show was over and reading would be impossible.

    At exactly 11:17, Brad called the daycare center(日托所).“I suddenly have to go into work and my wife is away. Can I bring the boys over in a few minutes?” The answer was obviously “yes” because Brad was smiling.

同类题2

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    In 1943, when I was 4, my parents moved from Coeur d'Alene, Idaho, to Fairbanks, Alaska, where adventure was never very far away.

    We arrived in the summer, just in time to enjoy the midnight sun. All that sunlight was fantastic for Mum's vegetable garden. Working in the garden at midnight tended to throw her timing off, so she didn't care much about my bedtime.

    Dad was a Railway Express agent and Mum was his clerk. That left me in a mess. I usually managed to find some trouble to get into. Once I had a little fire going in the dirt basement of a hotel. I had tried to light a barrel(桶) of paint but couldn't really get a good fire going. The smoke got pretty bad, though, and when I made my exit, a crowd and the police were there to greet me. The policemen took my matches and drove me home.

    Mum and Dad were occupied in the garden and Dad told the police to keep me, and they did! I had a tour of the prison before Mum rescued me. I hadn't turned 5 yet.

    As I entered kindergarten, the serious cold began to set in. Would it surprise you to know that I soon left part of my tongue on a metal handrail at school?

    As for Leonhard Seppala, famous as a dog sledder(驾雪橇者), I think I knew him well because I was taken for a ride with his white dog team one Sunday. At the time I didn't realize what a superstar he was, but I do remember the ride well. I was wrapped(包裹) heavily and well sheltered from the freezing and blowing weather.

    In 1950, we moved back to Coeur d'Alene, but we got one more Alaskan adventure when Leonhard invited us eight years later by paying a visit to Idaho to attend a gathering of former neighbors of Alaska.