Engine （） refers to the relative time of position of crank, at which each operation during the cycle is commenced and is completed.

Engage the flywheel with the （）.A.turning gearB.motorC....

单项选择题Engage the flywheel with the （）.

Energy losses due to （） occur in every machine.A.speedB...

单项选择题Energy losses due to （） occur in every machine.

Emulsion oils and sodium nitrite are both approved addi...

单项选择题Emulsion oils and sodium nitrite are both approved additives, but （） cannot be used if any pipes are galvanized or if soldered joints exist.