Rahim and john were two friends. once rahim went to visit the new house of john . to expel hot air out of the kitchen, john fitted an exhaust fan on his kitchen window. by seeing this , rahim said to john that an exhaust fan should place on the wall near his kitchen ceiling. otherwise, the exhaust fan will not expel the hot air more effectively. (a). is rahim right or wrong ? why?
(b). how a vantilator works in circulating fresh air in the room?

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