The interior of a rectangular carton is designed by a certain manufacturer to have a volume of x cubic feet and a ratio of length to width to height of 3 : 2 : 2.  In terms of x, which of the following equals the height of the carton, in feet?

~$\sqrt[3]{x}$~

~$\sqrt[3]{\frac{2x}{3}}$~

~$\sqrt[3]{\frac{3x}{2}}$~

~$\frac{2}{3}\sqrt[3]{x}$~

~$\frac{3}{2}\sqrt[3]{x}$~