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问题 问答题

如图1是小明用刻度尺测量一条形金属片长度的情形，该刻度尺的分度值是______，金属片的长度是______cm；图2中A、B是两种比刻度尺______的长度测量工具．

答案

（1）由图可知，在1cm之间由10个格，那么每一个小格就是1mm，即该刻度尺的分度值；

从图中可看出，测量的起始刻度不是零刻度，而是5.50cm的刻线，金属片末端对着的刻度线为8.30cm，所以金属片的长度即为两刻度值差L=8.30cm-5.50cm=2.80cm；

（2）图2中的测量工具分别是游标卡尺和螺旋测微器，都属于精密的测量工具，其分度值很小，测量结果的精确程度高．

故答案为：1mm；2.80；精确度高．

单项选择题

Are you a man or a mouse When people ask this question they want to know (1) you think you are a (2) person or a coward. But you will never really know the answer to this question (3) you are tested in real life. Some people (4) they are brave but when they come face to face with real (5) , they act like cowards. Others think of themselves as cowards, but when they meet danger, they act like (6) .Lenny had always thought of himself as a (7) person. He got worried before examinations. He worried about his job and health. All he wanted in life was to be safe and healthy. (8) , on January 15th, 2002, a plane crashed into the Potomac River in Washington. Lenny went to the river to See what was happening. He saw a woman in the (9) water. Lenny did not feel afraid. He kept very (10) and did a very dangerous thing. He jumped into the Potomac, (11) to the woman, and kept her head (12) the water. Seventy-eight people died that day. Thanks to Lenny, it was not (13) .When you are in a very (14) situation and feel afraid, the body automatically produces a chemical in the blood. The chemical is called adrenalin. (15) adrenalin in the blood system, you actually feel per and per and are (16) to fight or run away. However, when you are absolutely terrified, the body can produce too much adrenalin. Where this (17) , the muscles become very hard and you find you (18) move at all. You are then paralyzed with fear. This is (19) when we are very frightened, we sometimes say we’re "petrified". This word comes from the Greek word "petros", which means "stone". We are (20) frightened that we become stonelike.

 

第（14）空应选择（）

A．dangerous

B．comfortable

C．different

D．favorable
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单项选择题

在北半球，船舶穿越锋面气旋，当观测到云的变化次序为Ci-Cs-As-Ns-Ac-Cb，则可判定船舶从（）。

A．气旋中心附近以北，由东向西穿越

B．气旋中心附近以南，由东向西穿越

C．气旋中心附近以南，由西向东穿越

D．气旋中心附近以北，由西向东穿越
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