A.stop the engine by cutting off the cooling water supply
B.stop the engine by closing the air intake
C.slow the engine but not stop it
D.slow the engine to half of normal load

A.increase the liner area covered by the oil film
B.maintain an oil film on the lower liner where scuffing is prevalent
C.keep excess oil away from intake and exhaust ports
D.help cushion piston skirt side thrust by providing a hydrodynamic oil wedge