The Diaz sisters, Martina and Mar+¡a Eugenia, are in this country under the auspices of the Experiment in International Living, one of the oldest student exchange groups in the world, now celebrating it's 25th anniversary. The daughters of Raul Diaz Baren and Martina Andres de Diaz of Santiago, Chile, the sisters studied at Santiago College, an American school in Chile, made many American friends, and decided to visit this country. They chose to come here with the Experiment in International Living because it afforded them an opportunity to live with an American family...