The volume of the 3-dimensional structure formed by rotating the circle x^2 +(y−5)^2 =1 around the x-axis can be expressed as V=a*pi^2 . What is the value of a

Using Theorem of Pappas, knowing that the centroid is at (0,5),

v = 2pi (5) * pi * 1^2 = 10pi^2