Question $3(10$ points$)$

Obstruct building is $45ft$ away the centerline of the lane of a local road where vehicle $C$ was on$,b$ in the Figure, and $65ft$ away the centerline of the right lane of an intersecting road where vehicle A was on$,$ a in the Figure. The speed of the vehicle $A$ is $35$ mile$/$hour$.$ To find the maximum speed of vehicle $C$ allowable on the local road.

Hint: First find da with speed of $35$ mile$/$hour from Table $7\mathrm{.}7,$ then use equation $7\mathrm{.}4$ to find $db,$ finally to get the speed with $db$ from Table $7\mathrm{.}7$ again.