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.
A market economy is an economic system in which individuals own most of the resources - land, labor, and capital - and control their use through voluntary decisions made in the marketplace. It is a system in which the government plays a small role. In this type of economy, two forces - self-interest and competition - play a very important role.