All of the following are examples of the use of electromagnetic radiation except

refrigeration units

microwave ovens

radios

cell phones

Radio waves and microwaves are forms of electromagnetic radiation. Cell phones are basically glorified radios. Refrigerators work by coolant coming in contact with the hot parts, which is more thermal than electromagnetic.

Ithink it’s 3 as the answer.

All the elements are arranged by melting points on the periodic table. in row they go from metals to gasses. in the row from sodium to argon, sodium is more reactive than the one on its right, magnesium.