The Volume of Wood, V, Obtained from a Tree Varies $h$

Multiple Choice

The volume of wood, V, obtained from a tree varies jointly as the height, $h$ , and the square of the girth (the distance around the tree trunk) , g. If the volume is $38.4 \mathrm { ft } ^ { 3 }$ when the height is $30 \mathrm { ft }$ and the girth is $4 \mathrm { ft }$ , what is the volume when the height is $50 \mathrm { ft }$ and the girth is $6 \mathrm { ft }$ ?

A) $139.76 \mathrm { ft } ^ { 3 }$
B) $147 \mathrm { ft } ^ { 3 }$
C) $146.35 \mathrm { ft } ^ { 3 }$
D) $144 \mathrm { ft } ^ { 3 }$