Question

What happens to the area within the circle as the circle’s radius doubles? Triples? What happens if the radius grows to four times its original length?

Answer 1

Area = pi* R^2, where "pi" is a constant

Area is proportional to radius R squared.
If R is multiplied by 2, the area gets multiplied by 2^2 = 4. Just multiply the original area by 4.
The other answers are: 3^2 = 9 times and
4^2 = 16 times larger.