The power of a lens is +4D. What is the nature of lens

power 4d6. 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 cmMalaysia Live 4D Results for Sports ToTo, Magnum 4D, Pan Malaysia 1+3D, 6D (Da Ma Cai), Sabah Lotto 4D88, Sarawak Cash Sweep & Sandakan 4D. Toggle navation