well when thinking of gravity you have to think of the size and mass of the object so,
The sun (largest and most mass)
Earth
Earth's moon
Discover satellite (cause it's tiny and light compared to the sun!)
Let lowest possible score be x (66+ 80+ 88+ 82 +72+ x)/6=80 on solving we get ans as 92
Answer:
b)

Step-by-step explanation:
b) set up equations so they are equal to each other,



this is when f(x)=g(x) so our approximation was close.
c)solving it graphically is nearly impossible because the solution can be any value around the intersection. only way to be sure is to solve it symbolically.
Hopefully this will help you