An incident ray strikes a boundary at a 72.5-degree angle, resulting in an angle of refraction of 39.6 degrees. the index of refraction of the first medium is 1.0003. what is medium 1? what is medium 2?

Diego is trying to lift a piano to the second floor of his house. diego uses a pulley system and gives a big lift to the piano. the piano moves upward, then stops, and then it starts to fall to the ground. which list best describes the forces on the piano in the proper order? positive force → balanced force → negative force negative force → balanced force → positive force positive force → unbalanced force → negative force negative force → unbalanced force → positive force