Modulating dampers in air handling systems are used
a) as mixing boxes to proportion the amounts of two different air flows such as outdoor air and recirculated air
b) to modulate the volume of conditioned air needed to meet load requirements
c) as face dampers to modulate the volume of air that goes through a cooling or heating coil
d) as bypass dampers to throttle the balance of the constant total air flow around a heating or cooling coil
e) all of the above
Answer: E