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.
The Atomic Mass Number or simply the Mass Number of an atom is defined as sum of the number of the protons and the number of neutrons in the nucleus of the atom. The number of protons in the nucleus is called atomic number (Z). The total number of protons and neutrons is called mass number (A).