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 number is the number of protons in every atom of that element. The number of electrons can change, forming ions, or the number of neutrons can change, forming isotopes, but the proton number defines the element. The modern periodic table orders the element by increasing atomic number.