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.
For postage of a 1st class, 1 oz. envelope the cost is $0.49. For postcards the rate is $0.34. Click here to see more postage rates. For Save-the-Dates you can expect an average cost of $150 for 100 postcard STDâs.