常用的板料冲压设备有( )。 A.水压机 B.摩擦压力机 C.开式压力机 D.闭式

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问题:

常用的板料冲压设备有( )。

A.水压机

B.摩擦压力机

C.开式压力机

D.闭式压力机

E.平锻机

考点:注册资产评估师机电设备评估基础机电设备评估基础
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抛物线方程为y2=8x,其焦点为F,过F的直线l与抛物线交于两点A、B,它们的坐标分别是A(x1,y1),B(x2,y2),则x1x2=______,y1y2=______.

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“如果你要知道砒霜是否有毒,你就得亲口去尝一尝。”这句话错在

A.主张要学习书本知识与前人经验

B.否认了实践是检验认识真理性的唯一标准

C.否认了人们可以认识客观事物

D.否认了人们可以通过知识的学习和传递来获得知识

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B

The worst danger is a house on fire when people are asleep. Always be ready to leave through a window into the garden by making sure you can open it if necessary. If you should be on holiday in a tall building or hotel, make sure you know where the fire escape(太平梯) is. When you can’t find any way out, try to find pieces of cloth and make a rope to get out of a window to safety. If you smell burning in your home, get out right away. If you can’t breathe properly because of smoke on your way out, crawl(爬) on your hands and knees because smoke rises and the air will be cleaner near the floor. Smoke is a killer and more people die from breathing it in than actually being burned.

Fire in a cinema hall or public place often means people pushing to reach a door. Keep your head up with arms up in front of your chest. This protects your chest and gives you the best chance to breathe. Above all, don’t get frightened!

60. When a tall building is on fire, people______.

A.can leave by coming down the fire escape     B.should first check the room window

C.had better find a long rope                 D.must lie down on the floor at once

61. People can leave a burning house through a window if ______.

A.there is smoke in the room          B.  there is no other way out

C .they can’t breathe properly          D.  they want to put out the fire

62. There are several things to do to keep one safe. Which of the following is not talked about in the passage?

A.Leave the house right away when you smell something burning.

B.Raise your head and keep your chest from being hurt.

C.Get out of the house by crawling on the floor.

D.Rush out of the house, dressed in wet clothes.

63. Which of the following is not true?

A.In a fire, more deaths are caused by smoke.

B.The most important thing is not to be frightened in a fire.

C.When a public place is on fire, people usually push to leave.

D.Be ready to leave a burning house through a window if there is a garden down below.

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五倍子含较多鞣质,与黄连合煎可沉淀小檗碱,抗菌作用减弱。()

题型:多项选择题

铁的含碳量()%。

A.小于2.11

B.大于2.11

C.1.8

D.1.2

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