Question 7 1 pts What is the critical angle for monochromatic light travelling from a substance of refractive index n = 1.51 into another substance of refractive index n = 1.17? Give your answer to 1 decimal place. l l Question 8 1 pts A yellow light is placed at the bottom of a swimming pool lled with water (n = 1.33) and emits light in all directions. Standing above the water (in air, n = 1.00), a circle of light, with a radius of 0.83 m is seen on the water's surface. How deep is the pool? Give your answer to 2 decimal placas. E Question 9 1 pts Determine the image height (in cm) from a concave mirror with a focal length of 5.2 cm when the object distance from the lens is 11.2 cm and its height is 2.7 cm. Give your answer to 1 decimal place. If the object is inverted, then enter a negative number. Otherwise, enter a positive number