43. Points $A$ and $B$ are located on a straight highway running from west to east. Point $B$ is 9 km east of $A$. A car departs from point $A$ heading east at a speed of 40 km per hour. At the same time, a motorcycle departs from $B$ in the same direction with a constant acceleration of 32 km/hour ${ }^{2}$. Determine the greatest distance between the car and the motorcycle during the first two hours of travel.

Hint. It is useful to draw a graph of the distance as a function of time.