Answer:
The surface gravity is inversely proportional to the square of the radius of the planet
Explanation:
The gravity at the surface of a planet is given by:

where
G is the gravitational constant
M is the mass of the planet
R is the radius of the planet
We see from the formula that the surface gravity is inversely proportional to the square of the radius of the planet, R.
At the Earth's surface, the value of the surface gravity is approximately 9.81 m/s^2.
Answer:
Explanation:
If a perfect vacuum existed in any volume, then no sound would be able to propagate through it, because a sound wave is a pressure wave, and there would be identically zero pressure. Of course, we could get into speculations about “dark energy” or “vacuum energy” supporting pressure waves, but let’s not go there.
They have the same Number of protons