If Pure Polonium-210 (K = 5

question 1

Multiple Choice

If pure polonium-210 (k = 5.02 × 10^-3 day^-1) were used in a crime, based on radioactive disintegration alone, how long would it take for half the original isotope to disappear?

• A) 1.44 × 10³ minutes
• B) 69.3 hours
• C) 138 days
• D) 2.9 years
• E) 210 years

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