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.
The U.S. Postal Service allows customers to use the postcard rate for First-Class Mail for postcards that are at least 3.5 inches high by 5 inches wide but no more than 4.25 inches wide by 6 inches wide. As of April 2014, the postage rate for a postcard of this size is 34 cents. USPS also has a First-Class rate for large postcards that are no more than 6.125 inches high by 11.5 inches wide by 0.25 inches thick. These postcards cost 49 cents to mail as of April 2014. Learn more about Postal Services