题干

央视《是真的吗?》节目中,主持人做了“电池+口香糖锡纸=取火工具”的实验:取口香糖锡纸,剪成条状,将锡纸条带锡面的一端接在电池的正极,另一端接在电池的负极,很快发现纸条中间处开始冒烟,起火苗,如图所示.这是因为锡纸是____(选填“导体”或“绝缘体”),将它的两端直接接入电池正负极,就会造成____,迅速产生大量的热量,使温度达到锡纸的燃点而使之燃烧,锡纸中间剪成凹形,是为了增大此处的____(选填“电流”或“电阻”),使实验更易成功.

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导体,短路,电阻

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    A small boy at summer camp received a large package of cookies (饼干) in the mail from his mother. He ate a few, and then 1 the rest under his bed. The next day, after lunch, he went to his tent to get a cookie. The box was2

That afternoon a camp teacher, who had been 3of the theft (失窃), saw another boy sitting behind a tree eating the stolen 4 “That young man,” he said to himself, “must be taught not to 5

    He returned to the group and met the boy 6 cookies had been stolen. Billy, he said, “I know who stole your cookies. Will you 7 me teach him a lesson?”

    “Well, yes —8aren’t you going to punish him?” asked the puzzled boy.

    “No, that would only make him 9 you,” the teacher explained. “I want you to call your 10and ask her to send you another box of cookies.”

    The boy did 11the teacher asked and a few days 12 received another box of cookies in the mail.

    “Now,” said the teacher, ‘“the boy who stole your cookies is down by the lake.” Go down there and13your cookies with him.

    “But,” protested (抗议) the boy, “he’s the14

    “I know. But 15 it - see what happens.”

    Half an hour later the camp teacher saw the two come up the hill,16 The boy who had stolen the cookies was 17 to get the other to accept his jackknife (折叠小刀) in18for the stolen cookies, and the victim was just 19the gift from his new friend, saying that a few old cookies weren’t that 20 anyway.