Two thin prisms are combined such that they neither produce any average deviation nor do they cause any dispersion when white light is incident on the

Two thin prisms are combined such that they neither produce any average deviation nor do they cause any dispersion when white light is incident on the combination. Angle of one prism is `A = 2°` and refractive index of its glass for red, yellow and violet lights are 1.49, 1.50 and 1.51 respectively. Find the dispersive power of the glass of the other prism.