WASHINGTON (Reuters) - U.S. Senator Bill Nelson sent letters to the chief executives of 10 major U.S.-based airlines on Monday, urging them to cap airline fares for passengers fleeing Hurricane Maria so that confusion over cost does not delay evacuations, an aide said.  I urge you to begin the process now for implementing capped airfare,  Nelson said in his letter, noting that Maria is already a major hurricane.  Individuals and families should not be forced to delay or cancel their evacuation efforts because of confusion over the cost of airfare.  