What is the exact volume of the sphere

Ineed ! the person who answers and shows their work on they got the answer first will be marked the !

Write a polynomial function f of least degree that has rational coefficients, a leading coefficient of 1, and the given zeros. 3, 4+2i, 1+(sqrt)7 the answer is supposed to be: f(x)=x(^5)-13x(^4)+60x(^3)-82x(^2)-144x+360 what am i doing wrong?

Nikolas calculated the volume of the prism. his work is shown below.