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.
Highlights of Changes. Single-piece, 1-ounce First-Class Mail letters will increase $0.01, to $0.46 (additional ounces remain at $0.20). The price for mailing a First-Class Mail postcard will increase by $0.01 to $0.33 and the cost of a stamped postcard will increase by $0.02 to $0.37.