On a map whose scale is 400 miles to an inch and a half, a certain estate is represented by a rhombus having a 60∘ angle. The diagonal opposite 60∘ is 163 in. The area of the estate in square miles is:
<spanclass=′latex−bold′>(A)</span>32500<spanclass=′latex−bold′>(B)</span>31250<spanclass=′latex−bold′>(C)</span>1250<spanclass=′latex−bold′>(D)</span>256253<spanclass=′latex−bold′>(E)</span>12503