99 point question plus !
( answer genuinely, and do not answer just for point, if you do your answer will be deleted, and the points you earned, will be taken

using the disk, shell, or washer method from

find the volume of the solid generated by revolving the region bounded by the graphs of the equations about the y-

4.) 49-x^2; y=0
a.) v = 4pi * integral of(0 to 7) [ x(49-x^2) dx = 2401pi
b.) v = 2pi * integral of(0 to 7) [ x(49-x^2) dx = (2401/2)pi
c.) v = 2pi * integral of(-7 to 7) [ x(49-x^2) dx = (2401/2)pi
d.) v = 4pi * integral of(-7 to 7) [ x(49-x^2) dx = 2401pi

** explain your answer as much as possible (if you could, involve graphs), if you do not your explain how you got your answer, it will be deleted, and the points you earned will be taken
**reminder: this is calculus, not your basic