$(10$ points$)$ A major roadway with a speed limit of $45$ mph intersects with a minor

roadway at a right angle, with no intersection control. A building is located near the

intersection, $60$ feet from the center of the nearest lane on the major roadway and

$40$ feet from the center of the nearest lane on the minor roadway. At what speed for

the minor roadway is the intersection safe? Assume the grades are level.