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问题 单项选择题

只能用3.5MHz线阵探头扫查甲状腺，则补救方法为

A．侧卧位联合仰卧位扫查

B．多涂耦合剂

C．在探头与甲状腺之间加一个水囊

D．提供总增益

E．使用二维伪彩，增加图像对比度

答案

参考答案：C

解析：探头通过水囊可以去除近场的干扰，并有利于对甲状腺的整体进行观察，要注意和识别水囊的多次反射和假象。

多项选择题

Some commentators argue that: ‘With continuing pressure to control costs and maintain efficiency, the time has come for all public sector organisations to embrace zero-based budgeting. There is no longer a place for incremental budgeting in any organisation, particularly public sector ones, where zero-based budgeting is far more suitable anyway.’Required:

(b) Explain the terms ‘incremental budgeting’ and ‘zero-based budgeting’. (4 marks)
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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 where 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 table-cloth 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.

In this passage, inertia means ______.

A．a situation in which no action is taken

B．a situation in which no progress is made

C．the feeling of someone not wanting to move or do anything

D．the force making an object stay at rest or continue moving
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