为了满足工作要求,活塞销的材料一般选用______并经渗碳、淬火和低温回火处理。I、低碳钢(15钢),II、中碳钢(35钢),III、合金调质钢,IV、滚动轴承钢(GCr15),V、合金渗碳钢(20Cr)
A. I+II+V
B. I+V
C. II+V
D. I+III+V
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The desirable properties or a marine fuel oil should include_______.
A. high flash point and high viscosity
B. low flash point and high viscosity
C. low heating value and high sulphur content
D. high heating value and low sulphur content
活塞顶部烧蚀可采用_______进行测量
A. 塞尺
B. 深度游标卡尺
C. 测微尺
D. 样板和塞尺
滞胀是实际GDP________和价格水平________的结合。
A. 上升;上升
B. 上升;下降
C. 下降;上升
D. 下降;下降
E. 不变;上升
If a heavy sea strikes the rudder, the shock is transmitted through ___ to the rams, this
A. the control rod
B. the hunting gear
C. the floating ring
D. the tiller arm