Question

Match the following
1. an appliance that extracts heat energy from one source and deposits it elsewhere
2.a heating appliance that uses heat energy released from fossil fuels to warm water for use in radiant or convection heating systems
3. a machine that converts the internal energy of a fuel into mechanical energy
4. a machine that converts the internal energy of a fuel into mechanical energy
A.heat engine
B.heat pump
C.boiler
D.thermostat