When did adding candles to the birthday cake originate

If an atom has no charge, what can we say about the subatomic particles in the atom? a) there will be the same number of protons and neutrons, but a different number of electrons. b) there will be the same number of electrons and neutrons, but a different number of protons. c) there will be the same number of protons and electrons.

Which of the following has a positve charge? a) protons b) neutrons c) particles

In what year are the populations of china and india projected to be equal? 2023 2025 2027 2029