A spherical balloon with radius r inches has volume V (r) = 4 3 πr3. Find an expression that represents the amount of air required to inflate the balloon from a radius of r inches to a radius of r + 4 inches. (Express your answer in terms of π and r.)

So the question ask to formulate an expression to represent the amount of air required to inflate the balloon from a radius of R+4 and the expression would be V=16pi/3 * (3r^2+12r+16). I hope you are satisfied with my answer and feel free to ask for more if you have question and further clarifications