Which of the following molecules has a nonpolar covalent bond?
a. h–br
b. h–cl
c. h–f
d. h–h

D. H-H

With the other 3, one atom is more electronegative, drawing the electrons closer to it and making one side slightly positive, making it polar. With H - H, though, both atoms are the same, so the molecules are shared evenly and it is nonpolar.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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