A geochemist measures the concentration of salt dissolved in Lake Parsons, an isolated salt lake. He finds a concentration of 74. g. L measures the concentration of salt in several nearby non-isolated lakes, and finds an average concentration of 65 g-L -1 Assuming the salt concentration i Lake Parsons before it became isolated was equal to the average salt concentration in nearby non-isolated lakes, calculate the percentage of Lake Parsons which has evaporated since it became isolated. Be sure your answer has the correct number of significant digits.