A light beam is shone into a mystery material. The light beam has an incident angle of 48 degrees and a refracted angle of 27 degrees. If n1 = 1.00, what is n2? O 1.78 O 0.56 O 1.64 O 0.61 QUESTION 21 You are watching a live concert. You can also find the concert streaming live on Spotify. About how far must you stand from the stage in order for the live concert and the live stream to be perfectly in sync? HINT: Assume the radio signal (Spotify) has to travel all the way around the Earth. circumference of the Earth (average): 40,041,000 m Speed of sound: 345 m/s Speed of light: 300,000,000 m/s QUESTION 22 Suppose a roller coaster's first hill has a height of 60 meters. What is the maximum possible height of the first loop after the 60 m hill? HINT: What must the centripetal acceleration be equal to (or greater than) at the maximum height of the loop? Don't forget conservation of energy