The composition of the ancient atmosphere can be determined by analyzing bubbles of air trapped in amber, which is fossilized tree resin. (This is one way we know that the air in the time of the dinosaurs was richer in oxygen than our current atmosphere.) An air bubble appears to be 7.2 mm below the curved side of a piece of amber which has index of refraction 1.54. The length of the needle to reach the bubble is 10 mm. i. What is the radius of curvature of the amber