Question

Find A if r = 3.6 femtometers

Answer 1

I'm taking it that you want this in m^2
Area = pi r^2
r = 3.6 * 10^-15 meters
Area = 3.14 * (3.6 10^-15)^2
Area = 3.14 * 1.296 * 10^-29
Area = 4.069 * 10^-29