MCQM4813 · [1] A microwave oven heats food for a time entered on a keypad and then stops. A room heater switches off when a thermistor reading reaches the dial temperature. Which system is open-loop, and which uses a setpoint? Amicrowave oven | microwave ovenBroom heater | microwave ovenCroom heater | room heaterDmicrowave oven | room heater Next question →