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The radioactive isotope, tritium (³₁H) has a half-life of 12.3 years. If the initial amount of tritium is 32 mg, how many milligrams of it would remain after 49.2 years?

1. 8 mg
2. 1 mg
3. 2 mg
4. 4 mg

Correct answer: 2 mg

Solution

To find the amount of tritium remaining after 49.2 years, we can use the formula for radioactive decay: N(t) = N₀ * (1/2)^(t/t₁₂), where N(t) is the amount remaining, N₀ is the initial amount, t is the time, and t₁₂ is the half-life.

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