下列措施中,能增大摩擦的是 [ ]
A.在机器的轴上安装滚动轴承
B.雪后,在车轮上缠铁链
C.搬运机器时,在机器下面垫上圆木
D.给电风扇转轴加润滑油
答案:B
This article may shock some sensitive readers, I offer my apologies in advance. [ ]
A. from whom
B. for whom
C. to whom
D. towards whom
下列哪些船舶互见中按规则准许向右转向时应鸣放一短声:().Ⅰ、用机器推进的从事捕鱼的船舶;Ⅱ、限于吃水的船舶;Ⅲ、帆船;Ⅳ、从事拖带作业的船舶;Ⅴ、从事清除水雷作业的船舶
A.Ⅰ~Ⅴ
B.Ⅱ~Ⅴ
C.Ⅰ、Ⅱ、Ⅳ、Ⅴ
D.Ⅱ、Ⅳ