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.
Postcards get special pricing if you are mailing them at First Class Retail rates or, for bulk mailers, at Presorted First Class rates. First Class Retail postage for a postcard is just 34Â¢, compared with 47Â¢ for a letter, with similar discounts in Presorted First Class postcard rates. But here's the rub.