As of 2013, the United States spends about $554.2 billion annually to fund its military forces, and appropriates approximately $88.5 billion to fund Overseas Contingency Operations. Put together, the United States constitutes roughly 39 percent of the world's military expenditures.
the number of protons in the nucleus of an atom of a particular element. In a neutral atom, the atomic number equals the number of electrons. See also atom, electron, proton.
Hence, the difference between the mass number and the atomic number gives the number of neutrons (N) in a given nucleus: N=AâZ. The mass number is written either after the element name or as a superscript to the left of an element's symbol. For example, the most common isotope of carbon is carbon-12, or 12. C. , which has 6 protons and 6 neutrons. The full isotope symbol would also have the atomic number (Z) as a subscript to the left of the element symbol directly below the mass number: 12.