The 50,000 -lb flatear supports a 15,000 -lb vehicle on a $5^{\circ}$ ramp built on the flatear. If the vehicle is released from rest with the flatear also at rest, determine the velocity $v$ of the flatcar when the vehicle has rolled $s=40 \mathrm{ft}$ down the ramp just before hitting the stop at $B$. Neglect all friction and treat the vehicle and the flatcar as particles.