In an open system such as a campfire matter can

How much work would be needed to raise the payload from the surface of the moon (i.e., x = r) to an altitude of 5r miles above the surface of the moon (i.e., x = 6r)?

With i really need the correct answer!

A1,700kg car is being used to give a 1,400kg car a push start by exerting a force of 140n the impulse on the smaller car during the 30.0s of contact is +670kg*m/s. what is the impulse of the smaller car on the larger car? -814 kg*m/s 0kg *m/s -670kg*m/s -550kg*m/s