Answer:
d = 0.125 mm
Step-by-step explanation:
using snell's law


n₁ = 1 for air

r = 25.09⁰
displacement of color would be

for second color
using snell's law


n₁ = 1 for air

r = 22.58°
displacement of color would be

hence, separation is
d = 2.057 - 1.932
d = 0.125 mm