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问题 单项选择题 A1/A2型题

刺激腕部尺神经，用表面电极在小指展肌记录诱发电位的形状（）

A.起始为负相的三相波

B.起始为负相的双相波

C.起始为正相的双相波

D.单相波

E.多相波

答案

参考答案：B

单项选择题

If you left your book on the table overnight, you would find the following morning that it was still exactly when you had left it, provided nobody had moved it. If a ball is made to roll on a very smooth surface, it will roll a long distance unless something stops it or changes its direction. This tendency of an object to remain at rest unless something moves it and to continue moving unless something stops it is known as the Law of Inertia.
The following examples show the truth of this law.

  • (a) Put a table-cloth on a table and arrange a pile of books on it. Hold one edge of the tablecloth and pull it quickly. The table-cloth will come off, leaving the pile of books undisturbed.
  • (b) Place a small piece of cardboard on an open jar and place a coin on it directly over its mouth. Use one finger to flick the piece of cardboard away. You will notice that the coin drops into the jar.
  • (c) Sitting in a car which starts suddenly, you feel you are jerked backwards. In fact, you are not jerked backwards. Your lower half, which is in contact with the cushion, is forced to move forward with the car, and the upper part of your body, which remained at rest, is left behind.


The Law of Inertia is a law concerning ______.

A．motion

B．distance

C．position

D．direction
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单项选择题

根据《合同法》的规定，仓储合同的生效时间为（）

A.成立时起

B.存货人交付仓储物时

C.存货人支付仓储费时

D.保管人与存货人双方约定的时间
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