In the diagram shown, a plot between δ (angle of deviation) versus i (angle of incidence) for a triangular prism is given. From the observed plot, some conclusion can be drawn. Mark out the correct conclusion.

A
The range of deviation for which two angles of incidence are possible for same deviation is $δ_{0} - δ_{m}$
B
The curve is asymmetrical about $i_{0}$
C
For a given $δ$ , i is unique
D
Both 1 and 2 are correct.

The graph is asymmetrical about $i_{0}$ the section to the left of $i_{0}$ being steeper than the section to the right.

In the diagram shown, a plot between $δ$ (angle of deviation) versus i (angle of incidence) for a triangular prism is given. From the observed plot, some conclusion can be drawn. Mark out the correct conclusion.