Consider the microwave oven as an example of a discrete state process. The process variables that can be on or off include fan, light, timer, rotating base, microwave generator, and door switch. The process steps include opening the oven door/placing food inside, dosing the door, setting the timer, heating up food, and cooking completed. Prepare a table for each process step that shows the process variable status (on or off). What in- terlocks between variables are important safety issues?