Post-Traumatic Stress Disorder (PTSD) is a trauma and stress-related disorder that may develop after exposure to an event or ordeal in which death or severe physical harm occurred or was ...

Using relative and radiometric dating methods, geologists are able to answer the question: how old is this fossil?

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"Discount rate" has two distinct definitions. It can refer to the interest rate the Federal Reserve charges banks for short-term loans, but it's also used in future cash flow analysis.