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Why does the production of electron-positron pairs require less-energetic photons than the production of proton-antiproton pairs?
Department of Homeland Security
A federal agency established to secure the United States against threats, including terrorist attacks, natural disasters, and other emergencies.
Border Safety
Measures and policies implemented to protect a country's borders against illegal crossings, trafficking, and to ensure the security of its citizens.
Emergency Preparedness
The process of planning and implementing actions to prevent, respond to, and recover from natural disasters, accidents, or terrorist attacks.
Federal Reserve System
The Federal Reserve System is the central banking system of the United States, responsible for monetary policy, regulation of banks, and ensuring stability in the financial system.
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