往复式压缩机运转时,其止推轴承的主要作用在于()。
A、承受来自压缩机的作用力
B、承受来自驱动机的作用力
C、承受来自两个方向的作用力
参考答案:C
近视眼看远处物体像落在视网膜的______,近视眼镜的镜片是______透镜,它对光线具有______(选填“会聚”或“发散”)作用.
Questions 1~5
What can be concluded from the passage
A. Suicide is one of the top problems to be tackled in Japan.B. Economic development will give rise to social problems.C. The Japanese people cannot have their cake and eat it too.D. What the Japanese people are pursuing now is not true happiness.