Train $A$ is traveling at a constant speed $v_{A}=$ $35 \mathrm{mi} / \mathrm{hr}$ while car $B$ travels in a straight line along the road as shown at a constant speed $v_{B}$. A conductor $C$ in the train begins to walk to the rear of the train car at a constant speed of $4 \mathrm{ft} / \mathrm{sec}$ relative to the train. If the conductor perceives car $B$ to move directly westward at $16 \mathrm{ft} / \mathrm{sec},$ how fast is the car traveling?