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【单选题】
Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1. (10 points)10（）
A．seats
B．cabins
C．bodies
D．engines
A.
Air is (1) , and like all matter, it has weight. Weight is the measure of the (2) of gravity (3) matter. If a scale registers 10 kilograms when a stone is placed on it, this means that gravity pulls the stone with that (4) force. (5) , earth’ s gravity pulls on each (6) of gas and dust on the atmosphere. Because our atmosphere is a. vast (7) of air, it has (8) . If it could (9) be compressed and put on a (10) of scales, it would weigh about 5,700,000,000,000,000 (quadrillion) metric tons.
B.
The air pressed down on us and against us (11) all sides. Something (12) a ton of air is pressing against you at this moment. You are not (13) of this because air pressure within your body (14) the pressure of the air outside.
C.
Air pressure is 1. 036 kilograms per square centimeter (14.7 pounds per square inch) at sea (15) . It is greatest there because that is the (16) of the atmosphere. (17) higher altitudes the pressure is (18) . That is why the (19) of highflying planes are pressurized. They are designed to (20) the air pressure our bodies must have.
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【单选题】The arrival of computers everywhere in the workplace would，we were assured，soon make paper a thing of the past（）
A.
电脑铺天盖地出现在工作场所各处，我们深信有纸办公即将成为过去的事情。
B.
电脑出现在工作场所各处，我们确信，有纸办公很快会成为过去的事情。
C.
电脑铺天盖地出现在工作场所的各个角落，使我们深信有纸办公即将成为历史。
D.
我们确信电脑到达了办公场所各个地方，很快会使纸的生产成为历史。
【单选题】()trouble ahead.
A.
There seem to be
B.
There seems to be
C.
There seem to have
D.
There seems to have
【单选题】设f(x)=φ(x)(1+|sinx|)，φ(x)可导，则φ(0)=0是f(x)在点x=0处可导的（）
A.
充分必要条件．
B.
必要条件，但非充分条件．
C.
充分条件，但非必要条件．
D.
既非必要条件，又非充分条件．