True. Only the very large cities can afford to have full-sized conventional centers. True. Visits to national parks are increasing. True. Among all parks, theme parks are less in number, but earn more in receipt. False. Gambling in the United States is limited to Las Vegas and Atlantic City. False. Travel destinations more and destination of our exports. When our ... These two operations of selling our exports and buying our imports, are to be performed every year. The Twentieth Century The typical resort hotel in North America at the beginning of the twentieth century was a summer operation. ... Air travel was still costly, however, and relatively few could afford it.