题干

如图,平底茶壶的质量是200g,底面积是 50cm2 ,内盛 0.8kg 的水,水的深度为15cm,放置在面积为 2m2 的水平桌面中央 .(g=10N/kg) 试求:
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同类题2

阅读下面短文,从短文后各题所给四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑

    One day, I drove into a service station to get some gas. It was a beautiful day and I was feeling1. As I paid for the gas, the attendant said, “How do you feel?” that seemed like a2question, but I felt fine and told him so. “You don't look 3.” he replied and continued to tell me my skin appeared 4.

    By the time I left, I was a little 5. About a block away, I 6 to the side of the road to look at my face 7the mirror. Was everything all right? Had I picked up 8rare disease? By the time I got home, I was beginning to feel a slight 9somewhere in my body.

    The next time I went into that gas station, I 10 what had happened: The place had recently been painted a bright, bilious yellow, and the light reflecting off the walls made everyone inside 11as though they were sick! That was the truth. 12, I let that short conversation change my attitude for an entire day. His 13 observation affected the way I felt and acted.

    This experience made me think a lot. It is the same with life, in which attitude 14. The way we look at life determines how we feel and how we 15. If we expect something to turn out16, it probably will. But 17 also works in reverse. If we expect good things to happen, they 18do. An optimistic attitude, I believe, is not a luxury but a(an)19. So after that, I chose to highlight the 20throughout the rest of my life.

同类题3

阅读下文,回答问题

       ①松鼠是一种漂亮的小动物,驯良,乖巧,很讨人喜欢。

       ②它们面容清秀,眼睛闪闪有光,身体矫健,四肢轻快,非常敏捷,非常机警。玲珑的小面孔,衬上一条帽缨形的美丽的尾巴,显得格外漂亮;尾巴老是翘起来,一直翘到头上,身子就躲在尾巴底下歇凉。它们常常直竖着身子坐着,像人们用手一样,用前爪往嘴里送东西吃。可以说,松鼠最不像四足兽了。

       ③松鼠不躲藏在地底下,经常在高处活动,像鸟类似的住在树上,满树林里跑,从这棵树跳到那棵树。它们在树上做窝,摘果实,喝露水,只有树被风刮得太厉害了,才到地上来。在田野里,在平原地区,是找不到松鼠的。它们从来不接近人的住宅,也不呆在小树丛里,只喜欢大的树林,住在高大的树上。在晴明的夏夜,可以听到松鼠在树上跳着叫着,互相追逐的声音。它们好像很怕强烈的日光,白天躲在窝里歇凉,晚上出来练跑,玩耍,吃东西。它们虽然也捕捉鸟雀,却不是肉食兽类,常吃的是杏仁、榛子、榉实和橡栗。

       ④松鼠不敢下水。有人说,松鼠过水的时候,用一块树皮当作船,用自己的尾巴当作帆和舵。松鼠不像山鼠那样一到冬天就蛰伏不动。它们是十分警觉的,只要有人稍微在树根上触动一下,它们就从窝里跑出来,躲在树枝底下,或者逃到别的树上去。松鼠跑跳轻快极了,总是小跳着前进,有时也连蹦带跳。它们的爪子是那样锐利,动作是那样敏捷,一棵很光滑的高树,一忽儿就爬上去了。松鼠的叫声很响亮,比黄鼠狼叫声还要尖些。要是被人家惹恼了,还会发出一种不高兴的恨恨声。

       ⑤松鼠的窝通常搭在树枝分叉的地方,又干净又暖和。它们搭窝的时候,先搬些小木片,错杂着放在一起,再用一些干苔藓编扎起来;然后把苔藓挤紧,踏平,使那建筑物既宽广又坚实,可以带着儿女住在里面,既舒适又安全。窝口朝上,端端正正,很狭窄,勉强可以进出;窝口上有一个圆锥形的盖,把整个窝遮蔽起来,可以使雨水向四周流去,不落在窝里。