A: No, it doesn't. I use mine in my office at work.
A: Yes the unit will consume power when not in use.
A: That is the time of cooking
A: The top dial is to select the power level.
A: The top dial is the power level dial. In the 700W retro microwave, there are seven power levels: (I) gentle heating, 120W; (II) heat, 180W; (*) defrost, 270W; (IV) low, 390W; (V) medium, 500W; (VI) medium high, 610W; and, (VII) high or full power, 700W. For additional questions, the use and care manual can be accessed online at the Magic Chef site: https://images.thdstatic.com/catalog/pdfImages/85/8588444a-89d1-4fb6-96ad-8524bd1b517a.pdf
A: This unit has a combination of metal and plastic.
A: This is normal operation. The magnetron cycles while the unit is on.