题干

如图甲所示的九阳豆浆机,由打浆和电热两部分装置构成。中间部位的打浆装置是电动机工作带动打浆刀头,将原料进行粉碎打浆;外部是一个金属圆环形状的电热装置,电热装置的简化电路图如图乙所示,开关S可切换加热和保温两种状态,R1、R2是发热电阻,豆浆机的主要参数如下表。请解答下列问题:

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同类题2

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    I was wandering around the Albuquerque International Sunport Airport. My flight had been delayed and I heard an announcement: “If anyone near Gate A – 4 understands Arabic(阿拉伯语),please come to the gate immediately. ” Gate A – 4 was my own gate. I went there.

    An older woman was crumpled (蜷缩成一团的) on the floor, she reminded me of my grandmother.

    “Talk to her,” urged the flight agent. “We told her the flight was going to be late, and she did this.”

    I bent over to put my arm around the woman and spoke uncertainly. “Shu-dow-a, shu-bid-uck, habibti? She stopped crying. She thought the flight had been canceled. She needed to be in El Paso for a medical treatment the next day. I said, “You'll get there, just late. Who is picking you up? Let's call him.”

    We called her son. In English, I told him that I would stay with his mother until we got on the plane. She talked with him. Then we called her other sons just for fun. Then we called my dad, and they spoke for a while in Arabic and found out that they had several shared friends. After that, I called some Palestinian poets I know and let them chat with her.

    She was laughing a lot by then, patting my knee and answering questions. She pulled a bag of home-made cookies filled with nuts and topped with sugar from her bag and offered them to the women at the gate. To my amazement, no one refused. It was like a sacrament (圣餐). The traveler from Argentina, the mom from California, the lovely woman from Laredo —we were all smiling, covered with the same sugar.

    I looked around that gate and thought: This is the world I want to live in, one with no anxiety. This can still happen anywhere, I thought. Not everything is lost.

同类题4

阅读下面的说明文,回答后面小题。
      沿海和岛屿居民中的寿星为什么特别多
      目前世界上平均寿命最长的国家是瑞典、冰岛、荷兰、挪威和日本。我们会很容易发现,这些国家都是沿海国家或岛国。科学家研究表明,沿海地区的环境确实有利于人体健康。
      滨海地区面向海洋,海洋空气较内陆少受污染,空气中含有较少的有毒物质,而含有较多的人体必需的微量元素。空气中负离子特别丰富,可以改善人肺的换气功能,增加氧的吸收量和二氧化碳的呼出量,调节中枢神经系统的兴奋和抑制状态,刺激造血系统功能等等。这些对人体健康都十分有利。
滨海地区气候—般较温和湿润,即使北欧国家气候较寒冷,海滨地区—年中气温变化也不大,不像大陆性气候那样暴冷暴热,这对人的新陈代谢有好处。如我国海南岛,四面环海,气候温和,长夏无冬,秋春相连,空气新鲜,全年平均气温为23—25℃,而最高气温在35℃以上的天数却比大陆少10-20天。海南岛的百岁寿星比例高达1/100000,远高于全国的0.37/100000。同样,上海的长兴岛,也是夏无酷暑,冬无严寒,四面环水,四季常绿,空气中负离子浓度较高,岛上居民长寿者较多。
      滨海地区海产品丰富,食物种类繁多,有利于调节人体的营养平衡。如日本诲产品的人均消费量是世界上最多的,日本人的人均寿命也名列世界前茅。我国海南岛上的居民,饮食以大米、薯类、瓜菜和诲产品为主,很少吃动物脂肪。这种饮食结构和习惯也有利于长寿。
      滨海区居民能较充足地得到生命必需的元素,海水中有毒元素浓度很低,使他们能最大限度地降低非必需元素在人体内的累积速度。比如,专家们对上海市长兴岛人的头发进行了测定,发现锰和锌含量普遍高,铜、镍等微量元素含量馆低。医学家认为,锰和锌多对人体有利,铜、镍过量对人体不利。长兴岛独特的地理环境,使岛上的水源、土壤及农作物中均呈现锰、锌含量高,而铜、镍含量低的状况。
      世界上的高寿区除了在海滨、海岛之外,还有不少在宁静秀丽的山村,或寒带的内陆区。但是,如果将世界的居民分成滨海区与内陆区来比较,显然滨海区的长寿者更多。
(选自《十万个为什么》)