Volume = 4/3*pi*r^3 As diameter = 6 inches Radius = Diameter / 2 Radius = 6/ 2 Radius = 3 inches Putting the value of r in the formula : =4/3*pi*3^3 =4/3*pi*27 = 36*pi So according to above explanation, B) V = 36 π cubic inches , is the correct answer.