These piston rings are so badly worn that they must be （）.

[单选题]The piston rings if found worn out （） and supplied by shipchandler.A . must replaceB . must to be equippedC . has to be repairedD . have to be renewed

[单选题]The piston rings are manufactured with a diameter （） the bore of the cylinder.A . larger thanB . smaller thanC . equal toD . none of the above

[单选题]Among the rings of a piston the （） one is subjected to the greatest load and temperature.A . bottomB . middleC . topD . none of the above

[单选题]The upper piston rings m large, slow-speed, two-stroke/cycle diesel engines are most effectively lubricated by oil ____.A．fed from mechanical lubricatorsB．thrown off from the main bearingsC．supplied from wick fed drip lubricatorsD．flow from a centrif

[主观题]Thewriterwasso______inherworkthatshedidn’tnoticehimentertheroomA．)absorbedC)focusedB)abandonedD)centered

[问答题]根据下面资料，回答As we know, museums are buildings where many valuable and importan

[问答题]根据下面资料，回答As we know, museums are buildings where many valuable and importan

[问答题]根据下面资料，回答As we know, museums are buildings where many valuable and importan

[问答题]根据下面资料，回答As we know, museums are buildings where many valuable and importan

[问答题]根据下面资料，回答As we know, museums are buildings where many valuable and importan