Identify which one of these systems can be considered as constituting an isolated system. View Available Hint(s) Identify which one of these systems can be considered as constituting an isolated system. Two motorcycles colliding on a rubber surface offering a large friction force. The system is the two motorcycles and the rubber surface is external to the system. Two marbles colliding on a sandy beach. The two marbles are the system and the sandy beach is external to the system. Two pucks colliding on a sticky surface. The two pucks are the system and the sticky surface is external to the system. Two pucks colliding on a frictionless ice surface. The two pucks are the system and the ice surface is external to the system.