内燃机由哪两大机构和五大系统组成？
当数字影片声音大小不合适时，需要调整功率放大器音量进行纠正。
中国古典园林的两种基本类型是（）。 ["皇家园林","江南园林","私家园林","寺庙园林"]
The purpose of inert gas systems aboard tankers is to（）. ["allow sufficient oxygen in the tank to sustain life","prevent outside air from entering the tank","provide more discharge pressure","comply with pollution regulatio"]
Which of the listed fire extinguishers cannot be easily recharged aboard ship?（） ["Soda acid","Carbon dioxide","Dry chemical","Cartridge-operated Foam"]
为什么说鲁尔区是德国的“工业心脏”？
