When the outdoor temperature falls below the balance point, an air-to-air heat pump _____.

When the outdoor temperature falls below the balance point, an air-to-air heat pump _____.
 
  A) must be shut down
  B) can no longer extract heat from the outside air
  C) requires supplemental heat
  D) can produce more heat than the structure requires

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[Ques. 2] It is acceptable to vent a gas appliance through a masonry chimney as long as _____.
 
  A) a tile or metal liner of the correct size is used
  B) the chimney is inspected to ensure it is in good condition
  C) the furnace is common-vented with another gas appliance
  D) a double-wall vent connector is used at the chimney opening

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[Ques. 3] The Celsius scale is based on water boiling at a sea level temperature of _____.
 
  A) 100
  B) 180
  C) 212
  D) 265

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[Ques. 4] Which of these components is unique to the heat pump?
 
  A) Compressor
  B) Defrost timer
  C) Condensing coil
  D) Evaporator coil

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[Ques. 5] The net weight of a refrigerant cylinder is the _____.
 
  A) weight of the contents alone
  B) weight of the container alone
  C) combined weight of the container and its contents
  D) weight of the container, the contents, and any additional packaging