The angle between two mirror is 60o and is kept fixed. A ray is incident on one mirror at an angle 'i' as shown in figure . The angle 'i' is slowly increased from 0o to 90o. Net deviation suffered by the ray after two reflections is D. Which of the following plots for 'D' v/s 'i' is correct? (Answer ASAP)
(1) (2)
(3) (4)