Question

A radioactive sample has half-life of 3 years. The time required for the activity of the sample to reduce to $\frac{1}{5}$th of its initial value is about

• A. 7 years
• B. 15 years
• C. 5 years
• D. 10 years

Answer 1

Answer: (A)

7 years

Answer 2

The correct answer is (A) : 7 years.