Diagram shows a path of light from an object AB which is placed in front of a right-angled isosceles prism of critical angle 42. Choose the correct statements. Object 1. The angle of incidence of light at the surface PQ is 60. 2. If the image of the object AB is formed then the nature of the image with respect to object AB is upright. 3. The incident speed of light at surface PQ is less than that at surface QR 4. This prism is used to deviate light rays through 90