$\text { An open box of maximum volume is to be made from a square piece of material } 30$

Multiple Choice

$\text { An open box of maximum volume is to be made from a square piece of material } 30$ centimeters on a side by cutting equal squares from the corners and turning up the sides(see figure) . What is the domain of the function $V = x ( 30 - 2 x ) ^ { 2 }$ .

A) domain: $0 < x < \infty$
B) domain: 30
C) domain: $0 < x < 15$
D) domain: $0 < x < 30$
E) domain: 15