单项选择题
Cylinder liner cooling is often referred to as （）.
A.piston cooling B.sleeve cooling C.central cooling D.jacket cooling
单项选择题 Cross scavenging requires the fitting of （） to prevent air or exhaust gas escape when the piston is at the top of the stroke.
单项选择题 Crankshafts of medium speed engines are （） from a single piece of steel.
单项选择题 Cracks in the cylinders and cylinder covers may （） unequal heating.
