A. Convex lens
B. Concave lens
C. Concave-convex
D. None of the Above
Check Also
Carbon credits introduced in:
A Climate B Kyoto Protocol C Polymer Congress D None of these
A. Convex lens
B. Concave lens
C. Concave-convex
D. None of the Above
A Climate B Kyoto Protocol C Polymer Congress D None of these