Power 4D

power 4d4D88 | All 4D Real Time Live 4D Draw Results (Keputusan 4D) - Magnum 4D, Sports Toto 4D, Da Ma Cai, Sabah 88 Lotto 4D, Sarawak Special Cash Sweep 4D, STC6. A convex lens of power +6 D is placed in contact with a concave lens of power –4D. What will be the nature and focal length of this combination ? (a) convex, 100 cm (b) convex, 50 cm