А, 2. (Power Functions) Write down the formula of the function which gives the area A of a circle of radius r. (b) Using fomulas for circles of radius rı and rz, and areas Ai and Az, to complete this: A₂ (c) Using each of (a)'s function and (b)'s ratio and proportion result, how would we have to adjust the circle's radius if we want its area to triple? (d) The ratio A/A2 in (b) involving areas is "dimensionless". Why do we say this?