power 4dVIP POWER 4D MKTHE > · Join group. About this group. AKI AKI SCAMER TAK BOLEH COPY CARTA & NOS ORANG LAIN.A convex lens of power 4D is kept in contact with a concave lens of power 3D, the effective power of combination will be . View Solution; The power of a concave lens is 10 D and that of a