another ques.

Q5. A ray of sunlight enters a spherical water droplet (refractiv index = 4/3) at an angle of incidence 53° measured with respect to the normal to the surface. It is reflected from the back surface of the droplet and re-enters into air. The angle between the incoming and outgoing ray is [take sin53° = 0.8]

Q6. A cubical vessel with non transparent walls is so loacated that the eye of an observer does not see its bottom, but sees all of the front wall upto bottom corner D. Upto what height water should be poured into ther vessel for the observer to see an object O arranged at a distance of 10 cm from the corner D? The face of vessel is a= 40 cm.