平面任意力系平衡时可以列出3个独立的平衡方程。
A. 对
B. 错
_____________________________.
A. I work in a factory.
B. I read newspaper.
C. I have bought something for you.
D. I am very busy now.
__________________________.
A. Frank is a fast runner.
B. Nobody runs faster than Frank.
C. Frank is one of the fastest runners.
D. Frank runs as fast as all the others.
__________________________.
A. Buses are too few.
B. People like to ride bicycles more thantake buses.
C. More bicycles than buses are seen inthis city.
D. There are more buses and bicycles inthis city than cars.
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