A lens is made of of a glass with refractive index of 1.7. The spherical air-glass interface on the left side of the lens opens to the right with a radius of 10.0 cm, while the spherical glass-air interface on the right side of the lens opens to the left with a radius of 8.0 cm. The thickness of the lens is 2.5 cm. A beam of yellow light parallel to the optical axis is aimed towards the lens from a height of 2.0 cm above the optical axis at a distance of 4.0 cm to the left of the left-most interface. Find the incident and refracted rays at point A (air-to-glass interface) and point B (glass-to-air interface). Find the intersection of the refracted ray with the optical axis and label this point as FF or the focus. What is the focal length of the lens? Note that you need to draw the interfaces and normal lines, together with angles of incidence and refraction of the rays.