A water tank is in the shape of a right circular cylinder with a height of 20 feet and a volume of 320π cubic feet. What is the diameter, in

$${\frac{{\mathtt{320}}{\mathtt{\,\times\,}}{\mathtt{\pi}}}{\left({\mathtt{20}}{\mathtt{\,\times\,}}{\mathtt{\pi}}\right)}} = {\mathtt{16}}$$$${\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{4}} = {\mathtt{16}}$$  4=r   r*2=d   d=4*2=8              d= 8 feet

A water tank is in the shape of a right circular cylinder with a height of 9 feet and a volume of 225ππcubic feet. What is the diameter, in feet, of the water tank?