The answer is true because if you look at the question what does it say
63/29 Cu (copper-63)
65/29 Cu (copper-65)
24/12 Mg (magnesium 24)
25/12 Mg (magnesium 25)
26/12 Mg (magnesium 26)
6/3 Li (lithium 6)
7/3 Li (lithium 7)
The top number is the mass number and you find that by adding the number of neutrons and atomic number
The bottom number is the atomic number and it’s the number or protons
Gravitational Pull, is the answer. just like we orbit the sun, the moon orbits us. we act almost like a magnet, we follow the biggest guy as leader. if the sun dissapeared, we would die, but probably, we would start to revolve around jupiter as it is the biggest