What is a covalent compound? Describe and give an example.

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An atomic nucleus is composed ofa)protons.b)protons and neutrons.c)protons and electrons.d)protons, neutrons, and electrons.

Pls i will do pls imma diewhat forms white light? (4 points)a. combination of all wavelengths of ultraviolet light b. combination of all wavelengths of visible lightc. absorption of electromagnetic waves d. absorption of infrared rays