Three people are installing equipment. Cyrus is installing a heating system, Aletta is installing a cooling system, and Francis is installing a cooling system.
Which best describes the possible equipment they could install?
Cyrus is installing an air conditioner, Aletta is installing a furnace, and Francis is installing a heat engine.
Cyrus is installing a furnace, Aletta is installing a heat pump, and Francis is installing an air conditioner.
Cyrus is installing a heat pump, Aletta is installing a thermostat, and Francis is installing a furnace.
Cyrus is installing a thermostat, Aletta is installing an air conditioner, and Francis is installing a heat engine.