Conclusion - artificial intelligence :

If we can determine what the exactly state of the world will be after an agent's action, so we can say the environment is deterministic. In these cases, the state of the world after an action is dependent only on the state of the world before the react and the choice of action. If the environment is non-deterministic, then utility functions will have to informed guesses about the expected state of the world after possible actions if the agent is to correctly choose the best one. 

RHINO's world was non-deterministic because people moved around, and they move objects like chairs around there. In actual fact visitors tried to trick the robot by setting up roadblocks with chairs. Because this was reason why RHINO's plan was constantly simplified