Energy and friction?

a lady is travelling north when she enters a fateful intersection. When she reaches the centre of the intersection, another bumped into her. The other car remained joined together to her after the collision and skidded to a stop. The speed limit on both roads entering the intersection is 50mph. From the skid marks visible on the street, you determine that after the collision the cars skidded 56 feet at an angle of 30degrees north of east before stopping . The ladies car weighs 2600lbs and the other car weighs 2200lbs , where the drivers weight is included in both cases. The coefficient of kinetic friction for a rubber tire skidding on dry pavement is 0.8. Prove that the other driver speeding . Also show that the lady was under the speed limit.