题干

小明发现超市里的手扶式电梯无人站在上面时运动较慢,有人站在上面时运动较快.他据此画出了如图所示的电路(R是一个压敏电阻).他分析:当人站在电梯上,R的阻值变小,电磁铁的磁性变____ (选填“强”或“弱”),衔铁与触点____ (选填“1”或“2“)接触,电动机的转速变快,电梯运行变快.

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强,2

同类题1

阅读理解

    It was a cold night in Washington, D. C., and I was heading back to the hotel when a man approached me. He asked if l would give him some money so he could get something to eat. I'd read the signs "Don't give money to beggars." So I shook my head and kept walking.

    I wasn't prepared for a reply, but he said, "I really am homeless and I really am hungry! You can come with me and watch me eat!" But I kept on walking.

    The incident bothered me for the rest of the week. I had money in my pocket and it wouldn't have killed me to hand over a buck or two even if he had been lying. Flying back to Anchorage, I couldn't help thinking of him. I tried to rationalize (找借口)my failure to help by thinking government agencies, churches and charities were there to feed him. Besides, you're not supposed to give money to beggars.

    Somewhere over Seattle, I started to write my weekly garden column for The Anchorage Daily News. Out of the blue, I came up with an idea. Bean's Cafe, the soup kitchen in Anchorage, feeds hundreds of hungry Alaskans every day. Why not try to get all my readers to plant one row in their gardens dedicated to Bean's? Dedicate a row and take it down to Bean's. Clean and simple.

    The idea began to take off. Readers would fax or call me when they got something in their garden. Those who only grew flowers donated them. Food for the spirit.

    In 1995, the Garden Writers Association of America held their annual convention in Anchorage and after learning of Anchorage's program, Plant a Row for Bean's became Plant a Row for the Hungry. The original idea was to have every member of the Garden Writers Association of America write or talk about planting a row for the hungry sometime during the month of April.

    As more and more people started working with the Plant a Row idea, new changes appeared unexpectedly. Many companies gave free seed to customers and displayed the logo, which also appeared in national gardening publications. Row markers with the Plant a Row logo were delivered to gardeners to set apart their "Row for the Hungry."

    Garden editor Joan Jackson, supported by The San Jose Mercury News and California's nearly year-round growing season, raised more than 30,000 pounds of fruits and vegetables her first year, and showed GWAA how the program could really work. Texas fruit farms donated food to their local food bank after being inspired by Plant a Row. Today the program continues to thrive and grow.

    I am surprised that millions of Americans are threatened by hunger. If every gardener in America--and we're seventy million strong--plants one row for the hungry, we can make quite a decrease in the number of neighbors who don't have enough to eat. Maybe then I will stop feeling guilty about abandoning a hungry man I could have helped.

同类题4

先通读下面的短文,掌握其大意,然后在每小题所给的A、B、C、D四个选项中,选出可以填入空白处的最佳选项。

    Before Father's Day.I found my father was unhappy because he was out of work.I decided to make him happy by buying him a special Father's Day gift.

    One day after school I 1to the Agins which was known for fashions and styles.I told Agins that I was looking for a Father's Day present.

    “Do you think he'd like a2?”she asked.“I think he may.”I told her.

    She3 a Swiss watch and I told her that I would like it.

    “How much money do you have?”she asked.

    “4dollars.”I replied.

    “You're so lucky!” she told me.“It's only $ 11.You still have $ 1 for the5.”She packed the watch and I thanked for my business.and I rode off home with the gift under my arm.

    When my father opened the gift,he was very6.“Where did you get it?”

    “I bought it at the Agins.It cost me $ 11.”I said.My father was shocked into silence.

    Many years later,the watch cost several hundred dollars,7I appreciated (赞赏) how wonderful Agins had been to me.I always felt regretful (后悔的) that I never had a8 to thank her.

    “What really surprises me to this day...my daughter.” My father said,“Letting you have the watch for 11 dollars was unbelievable (不可相信的).But the fact that she let you leave the9with a dollar for the card was a touch (触动) of kindness.I'll never10it.”