JEE Main 2023 Physics question

Unpolarised light is incident on the boundary between two dielectric media, whose dielectric constants are 2.8 (medium – 1) and 6.8 (medium – 2), respectively . To satisfy the condition, so that the reflected and refracted rays are perpendicular to each other, the angle of incidence should be the value of is . (Given for dielectric media, = 1)