The amount if protons is the same as the amount of electrons, so it would be 8. The charge is -2. Look at oxygen in the periodic table.
Explanation:
Potential energy is the the relationship between work done height mass and acceleration due to gravity, because of this some objects also experience kinetic energy due to the factors mentioned above
(20/23) times 100 is 87%
now the answer asks for percentage ERROR
100-87 =13
so answer is C
