An 86 kg student is sitting in a rolling chair. To roll towards the trash can to throw away
her trash she throws her 27 kg backpack away from her at 6 m/s. What velocity will the
student roll away with?

Ahot-air balloon is 11.0 m above the ground and rising at a speed of 7.00 m/s. a ball is thrown horizontally from the balloon basket at a speed of 9.00 m/s. ignore friction and air resistance and find the speed of the ball when it strikes the ground.