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参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】The author cited the case of the pollen-sprayed milkweed leaves in Paragraph 3 to show______.
A.
GM foods may harm crops
B.
GM foods contain more protein
C.
GM foods can kill insects effectively
D.
GM foods also have a dark side
【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)14（） A．knowing B．sure C．feeling D．aware
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.
【单选题】下列关于集合的并运算的说法不正确的是（ ）。
A.
ALL防止UNION删除组合结果中的重复行
B.
在SQL语句中支持集合的并运算
C.
两个SELECT语句的查询结果中的列数可以不相同
D.
两个SELECT语句的查询结果中的对应列必须有相同的数据类型和宽度
【单选题】' It should be the other way round.' This means ' ______'.
A.
I should go to another place to fish
B.
The fish are moving away
C.
I like the fish to feed me
【单选题】According to Harris Miller, __________.
A.
many countries in the world are short of IT workers
B.
IT workers are essential to the industrial revolution
C.
IT workers are essential to the development of today' s society
D.
iron ore is as important as IT workers in the course of social development