1. What is the measured critical angle for a laser beam traveling from water to air? Compute an experimental value for the index of refraction for water using this measured angle. The critical angle is 64.080 O4. The index of refraction for water is n = 1.33. Use this value to calculate the theoretical critical angle for the laser traveling from water to air. Compare this value to the one you experimentally determined with a percent error calculation. Show you work.6. Plot a graph of sin(0;) versus sin(0,). Construct your graph on a computer program such as Microsoft Excel. If you do not have a graphing program installed on your computer, you can access one on the internet via the NCES website or the Online Chart Tool. 7. Add a linear trendline and display the equation on the graph. In the Error Analysis section of your report, combine the measured index of refractions from the slope and question 1 as an uncertainty range by averaging the two values and taking two-thirds the difference between them as uncertainty (e.g., 1.28 +/- 0.03). Estimate the precision level from the uncertainty range, the accuracy level from the accepted value for the water's index, and discuss whether any systematic errors seem present from this comparison.Table 3: Laser and Refraction Cell Data Incident Angle, 0; Refracted angle, OT Degrees Degrees) Sin0; (Degrees) Sin0 (Degrees) 0 0 0 0 5 5 0.0872 0.0872 10 11 0.1736 0.1908 15 13 0.2588 0.2250 20 17 0.3420 0.2924 25 24 0.4226 0.4067 30 27 0.5 0.4540 35 30 0.5736 0.5 40 35 0.6428 0.5736 45 40 0.7071 0.6428 50 43 0.7660 0.6820 55 48 0.8192 0.7431 60 50 0.8660 0.7660 65 52 0.9063 0.7880 70 54 0.9397 0.8090 75 55 0.9659 0.8192 80 57 0.9848 0.8387 85 60 0.9962 0.8660 90 65 0.9063