Answer:
≈ 16 g
Step-by-step explanation:
Half life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half of its initial mass.
Therefore;
New mass = Original mass × (1/2)^n, where n is the number of half lives
Thus;
New mass = 125 × (1/2)³
= 125/8
= 15.625
≈ 16 g
