You're driving down the highway not paying a lot of attention when you run into the back of a pickup truck. Right before you hit the truck you are traveling at 35 m/s and right after you are traveling at 30 m/s. You estimate that you hit the truck with a velocity of 6 m/s (the differences between your speeds) so that the truck's initial speed is about 29 m/s. If the mass of your car is 750 kg and the mass of the truck is 1250 kg, what was the speed of the truck after you hit it?