To find amplitude, measure a: the horizontal distance between consecutive crest positions b: the horizontal distance between a consecutive crest and trough c: the vertical distance from a crest to a trough d: the vertical distance from a crest to the rest positionnever mind, use this for free points. i already answered it.

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.