- Copper is a chemical element with the symbol Cu (from Latin: cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement.
- United States Secretary of Defense (Wikipedia)
The United States Secretary of Defense (SecDef) is the head of the United States Department of Defense (DoD), the executive department of the U.S. Armed Forces, and is a high-ranking member of the federal cabinet. The SecDef’s position of command and authority over the military is second only to that of the president of the United States, who is the commander-in-chief. This position corresponds to what is generally known as a defense minister in many other countries. The president appoints the SecDef with the advice and consent of the Senate, and is by custom a member of the Cabinet and by law a member of the National Security Council.