What is an isotope?

A. Atoms of the same element that have different numbers of neutrons
B. Atoms of different elements that have different numbers of neutrons
C. Atoms of the same element that have different numbers of protons
D. Atoms of different elements that have different numbers of protons

According to newton’s law of universal gravitation, which statements are true? as we move to higher altitudes, the force of gravity on us decreases. as we move to higher altitudes, the force of gravity on us increases. as we gain mass, the force of gravity on us decreases. as we gain mass, the force of gravity on us increases. as we move faster, the force of gravity on us increases.