【简答题】When a sound is made just using air, it is called ‘_____________’; when a sound is made using one’s voice or vibration in the voice box, it is called ‘________’.
【单选题】For the proper control of the air temperature in an air conditioning system using chilled water circulation, which of the listed conditions should remain constant regardless of load changes? .
A.
Chilled water system supply temperature
B.
Chilled water system return temperature
C.
Compressor discharge temperature
D.
Compressor suction pressure
【单选题】Which of the following is true about using air carriers as a transportation mode when shipping products?
A.
Air carriers are the most cost-effective way to ship non-perishable goods over short distances.
B.
Air carriers are the slowest and least reliable modes of transport.
C.
Air carriers provide in-transit services such as the processing of goods en route.
D.
Air carriers are ideal when time is short and speed is needed.
【简答题】the air when it moves
【单选题】法兰克福车展是世界规模最大的车展 ,有 “汽车奥运会 ” 之称 。 那它是 每 ( ) 年举办一次。
【单选题】创办于()年,1951年移到法兰克福举办,每2年举办一次,9月在德国法兰克福举行,轿车和商用车轮换展出。它是五大车展中技术性最强的,被誉为是最安静的车展。
【单选题】Many restaurants have stopped using trans fats because they may______.
A.
pollute hydrogenated oils
B.
cause the food decay quickly
C.
raise the risk of heart attack
D.
spoil the taste of food
【简答题】A) When the warmer air meets with the cooler air. B) When the wind moves faster than 30 meters a second. C) When the seawater evaporates into the air. D) When the air gets wanner and warmer.