The advantage of the backward curved centrifugal fan over the forward curved centrifugal fan is that ...

The advantage of the backward curved centrifugal fan over the forward curved centrifugal fan is that
 
  A) backward curved fans are normally quieter in operation
  B) backward curved fans are non-overloading
  C) backward curved fans operate at lower RPMs
  D) backward curved centrifugal fans are well suited for small airflow quantities

 Q. 2

Hot water heating coils should be piped
 
  A) with PVC pipe to take advantage of PVC's natural insulating ability
  B) for parallel flow so that the warmest water meets the coldest air
  C) with iron pipe for durability and strength
  D) for counter flow so that the warmest water meets the warmest air

 Q. 3

Immediately after making adjustments to an air handler, it is important to check
 
  A) The blower motor amp draw under load B) The return air temperature
  C) The outdoor ambient temperature D) The compressor shell temperature