Apply the principles of this section to solve each of the following problems.
Imagine that a certain Mr. D. has been visited by a certain Mr. L. from elsewhere in the universe. Mr. D. and Mr. L. are alike in every way, except that they are non congruent mirror images! You have to introduce each of them at an international press conference, but neither will agree to give his name. How would you tell them apart? (There may be several ways.)