周转轮系中自由度为2,轮系是()。
A. 行星轮系
B. 差动轮系
C. 混合轮系
D. 无法确定
周转轮系的转化机构是一定轴轮系。()
A. 对
B. 错
What kind of medal did Liu Jiayu claim at Pyeongchang Winter Olympics?
A. Gold medal.
B. Silver medal.
C. Bronze medal.
D. No medal.
Which of the following is TRUE?
A. This is the first medal claimed by LiuJiayu.
B. This is the first gold medal claimed by Liu Jaiyu.
C. Liu Jiayu snatched the first medal for China at the Pyeongchang Winter Olympics.
D. Liu Jiayu snatched the first medal for women at the Pyeongchang Winter Olympics.