The Radioactive Isotope Bismuth-210 Has a Half-Life of 5 Days $t$

question 14

Multiple Choice

The radioactive isotope Bismuth-210 has a half-life of 5 days. Suppose we have an initial amount of 100 mg. The amount of Bismuth-210 remaining after $t$ days is

• A) \(100 \left( 2 ^ { 0.2 t } \right)\)
• B) \(5 \left( 2 ^ { 0.2 t } \right)\)
• C) \(50 \left( 2 ^ { - 0.2 t } \right)\)
• D) \(100 \left( 2 ^ { - 0.2 t } \right)\)
• E) \(100 \left( e ^ { 0.2 t } \right)\)
• F) \(5 \left( e ^ { 0.2 t } \right)\)
• G) \(50 \left( e ^ { - 0.2 t } \right)\)
• H) \(100 \left( e ^ { - 0.2 t } \right)\)

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