Given:Refractive index for red light,μr​ = 1.56Refractive index for yellow light, μy​ = 1.60Refractive index for violet light, μv​ = 1.68Angle of prism, A = 6°(a)  Dispersive power (ω) is given byω=μy​−1μv​−ur​​ On substituting the values in the above formula, we getω=(1.60−1)(1.68−1.56)​=0.600.12​=0.2(b) Angular dispersion ==0.600.12​=0.2 (μv​−μr​) =0.600.12​=0.2 =0.600.12​=0.2 A  =(0.12) × 6° = 0.72°Thus, the angular dispersion produced by the thin prism is 0.72°.