A. 相同 B. 不相同
A. 内力不同 B. 内力相同 C. 与内力无关
A. 内力图 B. 变形图 C. 内力方程 D. 控制截面内力
A. 伸长 B. 缩短 C. 不变
A. 应力不同 B. 内力不同
A. It provides you with a fitness assessment after training. B. It offers you a customized training plan. C. It allows you to work out without any fees. D. It asks you to work out on your own.
A. Its price is quite good. B. Its time is enough. C. Its classes are no-risk. D. Its trainers are experienced.
A. News report. B. Speech. C. Announcement. D. Advertisement.
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