单项选择题
The designed （） is 20 tons per day, but the fresh water generator can only distil 15 tons at present.
A.displacement B.weight C.power D.capacity
单项选择题 The defective places in the furnace （） with fire bricks.
单项选择题 After fitting back in place the gear wheels, don’t forget to （） them.
单项选择题 What separate the high pressure side from the low pressure side in a refrigeration system?（）
