Four squares ABCD, EFGH, IJKL, and MNOP are constructed such that points E, F, G, H are middle points (midpoints) of the sides o
f square ABCD. Points I, J, K, L are midpoints of the square EFGH. M, N, O, and P are midpoints of the square IJKL. What is the area of the square ABCD, if OP=2 cm?