264) When there is an addition of water vapour to the air of enclosed space, a gain in __________ is said to occur.

265) The relative humidity __________ as air gets drier.

266) The central air conditioning system has __________ overall efficiency as compared to individual systems.

267) The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body. This statement is known as

268) An ordinary passenger aircraft requires a cooling system of capacity.