A large urn contains 100 balls, of which 36% are red and the rest are blue. How many of the blue balls must be removed so that the percentage of red balls in the urn will be 72%? (No red balls are to be removed.)<spanclass=′latex−bold′>(A)</span>28<spanclass=′latex−bold′>(B)</span>32<spanclass=′latex−bold′>(C)</span>36<spanclass=′latex−bold′>(D)</span>50<spanclass=′latex−bold′>(E)</span>64