A black hole is a very dense, massive, body, left behind after a large star explodes. It has a huge gravity which will attract everything that comes near it, even light!
If youre looking for speed the equation would be distance/time
First body:
Second body:
From description of the task we have:
Population density<span> (in agriculture: standing stock and standing crop) is a measurement of </span>population<span> per unit area or unit volume; it is a quantity of type number </span>density<span>. It is frequently applied to living organisms, and most of the time to humans.</span>
