"D. Both have electrons that orbit the atomic nucleus in a similar way ." is not shared by Bohr's model and the modern atomic model.
Hope this helps,
Davinia.
Complete Question
A proton is located at <3 x 10^{-10}, -5*10^{-10} , -5*10^{-10}> m. What is r, the vector from the origin to the location of the proton
Answer:
The vector position is 
Explanation:
From the question we are told that
The position of the proton is
Generally the vector location of the proton is mathematically represented as

So substituting values

I think the answer is A because it is gravity that caused the planets to form and start orbiting around the nearest star which is the sun
It'd be an unbalanced force
The correct answer is D.
A nucleon<span> is one of either of the two types of subatomic particles (neutrons and protons) which are located in the nucleus of atoms.
</span>
The total number of nucleon in the nucleus of an atom gives you an idea about the mass of that atom. In fact, one may refer mass number as nucleon number.
Simply put, nucleons are the particles that make nucleus of an atom and are held up together inside the nucleus due to nuclear force.