题干

有若干标有“6V  0.5A”的小灯泡;此小灯泡正常发光时的电阻为  ____Ω,电功率为  ____W,若把两个这样的灯泡分别串联、并联后分别接在6V的电源上,则两种情况下电路的总功率之比为 ____

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12,3,1:4

同类题2

阅读下面文言文,回答问题

    子犹曰:贫者,士之常也,俭者,人之性也。贫不得不俭,而俭者不必贫,故曰“性也”。然则俭不可乎/曰/吝不可耳/夫俭非即吝/而吝必托之于俭俭而吝,则虽堆金积玉,与贫乞儿何异?

    粤西韦广为御史归,贫甚,居荒村。故人按部,广意其必来访,无所得馔,自渔于江。故人至,驺从既过,广登岸即,逾后垣入,衣冠肃客,客曰:“公何汗流渍发?”广曰:“适在近村,闻公至,竭蹶趋迎故耳!”左右窃笑曰:“绝似江中打渔人。”

    郑余庆极清俭。一日,忽召亲朋官数人会食。众皆惊讶,侵晨赴之。日高,余庆方出,闲话移时,众腹己枵。余庆呼左右曰:“分付厨家烂蒸去毛,莫拗折项!”众相,以为必蒸鹅鸭之类。又久之,盘出,酱醋亦极香新。但见每人前下粟饭一碗,蒸葫芦一枚,皆匿笑强进。

    王罴性俭率。镇河东日,尝有台使至,罴为设食,乃裂去薄饼缘。罴曰:“耕种收获,其功已深,舂爨造成,用力不少。之选择,当是未饥!”命左右撤去之,使者愕然。又尝与客食瓜,客削瓜皮侵肉稍厚,罴就地取食之。

(节选自冯梦龙《古今笑·贫俭部》)

【注】①子犹:冯梦龙,明代文学家,著有《古今小说》等。②馔(zhuàn):饮食;③驺(zōu):掌管车马的人;④枵(xiāo):饥肠辘辘;⑤缘:边缘;⑥舂爨(chōnɡcuàn):舂米做饭

同类题3

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A Book Review—The Snake-Stone by Berlie Doherty

    The setting: Urban England (the cities), but also rural England (the countryside) including remote English villages.

    The theme: The main theme is a teenage search of self-discovery, in this case the search for a mother from whom the hero was separated at an early age. Its other concerns are love, getting on with others, being persistent and courageous and trying to deal with doubts, troubles and worries. As the book moves to a close, James' swimming coach says to him: “You are not like a kid obeying instructions any more. You are diving like a young man who knows where he is going.”

    The characters: James is the hero of the story. He is a championship diver, and has a comfortable life with his foster parents (养父母). Yet he also has the qualities to take him on a long journey to find his birth mother. The other characters in The Snake-Stone, James' parents, his diving instructor, best friend, the villagers, people he meets on his journey, are pictured realistically.

    The turning point: The turning point in the story comes while James' foster parents are away in London, and he wonders about the identity of his birth mother. The only clue he has is a fossil, “the snake stone” which she left behind along with a note on which she had written: “Take good care of Sammie. It was written on a torn envelope with parts of an address still there.

    The journey: Instead of going to London, James decides to find his birth mother. With help from his geography teacher, James sets out for the remote country village where his mother might be found. James has painful, challenging, but also humorous and happy travels. The mother he finally meets, Anne, has a minor yet powerful voice in the novel. He comes to understand why she left him at a stranger's door fifteen years before. Although the meeting is not long, it leaves him with a feeling of completeness. As a journey of self-discovery The Snake-Stone also provides its readers with a happy ending. Its hero says, on returning to his foster parents, “I was home.”