An artificial odor is added to natural gas so that people can tell whether or not gas is leaking.
查看答案
Once football season begins, Matt starts jogging every night—to the refrigerator during commercial breaks.
A. I
B. P
C. E
The first person to die of radiation poisoning was a co-discoverer of radium, Marie Curie.
A. I
B. P
C. E
平面任意力系向作用面内任一点简化后,所得到的作用于简化中心的那一个力,一般来说不是原力系的合力。
A. 对
B. 错
平面任意力系向作用面内任一点简化得到的力和力偶,其中的任何一个与原力系都不等效。
A. 对
B. 错