单项选择题 The pump used to send the bilge water into the oily water separator（）the mixture because this might create finer oil particles.

单项选择题 The rising velocity of the globules carries them upwards where they become trapped by the under surfaces of plates and （）until the enlarged globules have sufficient rising velocity to travel along the plate surface and break away at periphery.

单项选择题 Humans are still needed to monitor the condition of the boiler all the time the latter is operated, （）it is just to acknowledge an alarm buzzer or flashing light in a control room.