- Statement A is correct. For a spherical mirror, the radius of curvature (R) is twice the focal length (f), i.e., R = 2f. - Statement B is incorrect. The power of a lens (P = 1/f) is positive for a converging lens (convex lens) because its focal length (f) is positive. The power of a diverging lens (concave lens) is negative because its focal length (f) is negative. - Statement C is correct. A plane mirror can be considered as a part of a spherical mirror with an infinite radius of curvature. Consequently, its focal length (f = R/2) is also infinite. - Statement D is correct. According to Snell's Law, when light travels from a denser medium (higher refractive index n₁) to a rarer medium (lower refractive index n₂), it bends away from the normal. This means the angle of refraction (θ₂) is greater than the angle of incidence (θ₁), as n₁ sin θ₁ = n₂ sin θ₂ and n₁ > n₂, implies sin θ₂ > sin θ₁, leading to θ₂ > θ₁.