The area of Zambezi's basin is 1,390,000 km2.
  Each sector is approximately triangular in shape, and the sectors can be rearranged to form an approximate parallelogram
  The are was the original unit of area in the metric system, with:1 are = 100 square metresThough the are has fallen out of use, the hectare is still commonly used to measure land:1 hectare = 100 ares = 10,000 square metres = 0

