How many stamps does it take to sent a business letter from California to Vermont?

One of the best things about America is from coast to coast one US stamp (that as of June 2010 costs 42 cents) will get your letter to where ever it is addressed, provided it weighs an ounce or less and the envelope size is between from 3.5" x 5" and 6.125" x 11.5" Letters sent in large format envelopes (No more than 12 inches high by 15 inches long ) start at $0.88 for the first ounce or less.