单选题Cold clearances between the skirt of an aluminum piston and the cylinder liner is about （）Atwice as large as with a cast iron pistonBthe same size as with a cast iron pistonChalf as large as with a cast iron pistonDthe same size as the crown of an aluminum piston
单选题
Cold clearances between the skirt of an aluminum piston and the cylinder liner is about （）
A
twice as large as with a cast iron piston
B
the same size as with a cast iron piston
C
half as large as with a cast iron piston
D
the same size as the crown of an aluminum piston
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