单项选择题
A.manoeuvring operations B.bad combustion C.cooling D.mooring trial
An aluminum piston has lower inertia and higher coeffic...
单项选择题An aluminum piston has lower inertia and higher coefficient of （） compared to that of cast iron.
A.viscosity B.twisting moments C.inertia D.thermal expansion
Among the rings of a piston the （） one is subjected to ...
单项选择题Among the rings of a piston the （） one is subjected to the greatest load and temperature.
A.bottom B.middle C.top D.none of the above
Aluminum pistons have （） coefficient of thermal expansi...
单项选择题Aluminum pistons have （） coefficient of thermal expansion compared with those of cast iron.
A.higher B.lower C.the same D.none of the above
