There is a metal screen on the front window of a microwave oven. This screen is essential because it
A. prevents electric charge from accumulating on the window.
B. prevents the glass from breaking in response to the rapid heating of its inner surface and the thermal stresses that result.
C. protects the window from splatters that may occur when food inside the oven boils.
D. reflects microwaves and keeps them inside the oven.
Answer:D
There is a metal screen on the front window of a microwave oven. This screen is essential because it
A. prevents electric charge from accumulating on the window. B. prevents the glass from breaking in response to the rapid heating of its inner surface and the thermal stresses that result. C. protects the window from splatters that may occur when food inside the oven boils. D. reflects microwaves and keeps them inside the oven.