Sanya has a piece of land which is in the shape of a rhombus (See Fig.
). She wants her one daughter and one son to work on the land and produce different crops to suffice the needs of their family. She divided the land in two parts by joining its opposite comers. If the perimeter of the land is 400 m and one of the diagonals is 160 m, how much area each of them will get to work on.