A planoconvex lucite lens 3.2 cm in diameter is placed on a flat piece of glass as in the figure 34-18 in the textbook. When 600 nm light is incident normally, 43 bright rings are observed, the last one right at the edge. 1.) What is the radius of curvature of the lens surface? Express your answer using two significant figures. 2.) What is the focal length of the lens? Express your answer using two significant figures.