The colors of visible light, often referred to as ROY G BIV (for red, orange, yellow, green, blue, indigo, and violet), are a small portion of the entire electromagnetic spectrum. Light can be thought of as a stream of packets of energy called photons.
The United States has a mixed economy and has maintained a stable overall GDP growth rate, a moderate unemployment rate, and high levels of research and capital investment. Its seven largest trading partners are Canada, China, Mexico, Japan, Germany, South Korea, and the United Kingdom.
Traditional economy. Traditional economy is an original economic system in which traditions, customs, and beliefs help shape the goods and the services the economy produces, as well as the rules and manner of their distribution. Countries that use this type of economic system are often rural and farm-based. Also known as a subsistence economy, a traditional economy is defined by bartering [citation needed] [dubious â discuss] and trading.