1- A 6500 kg truck traveling at + 7 m /s collides head with a 2500 kg car have traveling with a velocity of - 3 m/s . the truck and the car entangle and move together after the collision as shown in figure below . Find : BEFORE AFTER a ) What is the velocity of the truck and the car immediately after the collision . b ) Fill the table below before and after the collision .

Which statement is true? a) the work done to lift an object 6 meters is greater than the gravitational potential energy it gains. b) the work required to push an object is less than the work required to pull an object the same distance. c) the work required to raise an object to a height is equal to the gravitational potential energy the object gains. d) the work done against gravity to lift an object straight up is greater than the work required to roll it up a ramp.