Convert the following formula into a C$++$ expression: V$=4/3\backslash$pi r$3$

Convert the following formula into a C$++$ expression: V$=4/3\backslash$pi r$3$

V$=4/3*$ M$\_$PI $*$ pow$($r$,3)$;

$(4/3)*($M$\_$PI$)*$ pow$($r$,3)$;

V$=4\mathrm{.}0/3\mathrm{.}0*$ M$\_$PI $*$ pow$($r$,3\mathrm{.}0)$;

$(4/3)($M$\_$PI$)($r$**3)$;