A Radioactive Material Initially Is Observed to Have an Activity

question 58

Multiple Choice

A radioactive material initially is observed to have an activity of 1 600 decays/s.If six hours later it is observed to have an activity of 400 decays/s,what is its half-life?

• A)six hours
• B)three hours
• C)twelve hours
• D)seven hours
• E)​not enough information

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Definitions:

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