[[We see a line of code.]]
volume(r) = (r
int(pi))*pi*r^int(pi)
Programming tip: the number "3" is cursed. Avoid it.

{{Title text: If replacing all the '3's doesn't fix your code, remove the 4s, too, with 'ceiling(pi) 
 floor(pi) * pi * r^floor(pi)'. Mmm, floor pie.}}