The red wavelengths of light are the longer wavelengths and the violet wavelengths of light are the shorter wavelengths. Between red and violet, there is a continuous range or spectrum of wavelengths.
The USPS also includes that a large postcard is 49 cents to mail. The maximum size for this postcard is 11 1/2 inches long, 6 1/8 inches high and 1/4 inch thick. This is the same rate to mail a First Class 1 ounce letter domestically. The rates for postage increased as of January 2014.
On Sunday, Jan. 26, the cost to mail a first-class single-piece letter jumped from 46 cents to 49 cents. The U.S. Post Office's 3-cent increase is the largest hike for consumer postage in more than a decade. The cost of mailing a postcard will also go up to 34 cents, a 1-cent increase. The announcement of the increase in postage rates came Dec. 30. The increase will help the budget deficit that the USPS has been dealing with in recent years.