Suppose the designated speed for an exit ramp on a highway is to be $13.4\; m/s$ and the radius of the curve is $50.0\; m$. At what angle should the curve be banked? (i.e, the roadway is tilted towards inside of the curve).
$\begin{array}{1 1} 12.2^{\circ} \\ 20.1^{\circ} \\ 4.8^{\circ}\\ 2.9^{\circ}\end{array}$