Solution to problem 14 plz help in physics plz help asap

The question says that the prism is equilateral so angle of prism is π/3 . Also the angle of incidence = angle of emergence Which is equal to 3/4 of angle of prism which is equal to π/4. In your question answer is (d) part.using the formula A+d = i + e Where d= angle of deviation a= angle of prism I{angle of incidence}e (angle of emergence)Thus d = π/6