Can someone please explain to me how Radicals work? For example:

3⎷12

⎷72

Find a.
3⎷7 = ⎷a
a =

How would you simplify these?

Witch represents the inverse of the function f(x)=1/4x-12

The diameter of the moon is about 3500 km. approximate the surface area of the moon using the formula for the surface area of a sphere, s = 4? r^2. write your answer in scientific notation.

Who ever answers this will get a cookie from batman