Answer:
t(half-life) = 1600 yrs
Explanation:
All radio decay follows 1st order kinetics and therefore can be applied to the expression A = A₀e^(-kt)
A = current activity
A₀ = initial activity
k = decay constant
t = time of decay
Half-Life = 0.693/k
k = ln(A/A₀) / -t = ln(0.25) / -3200yrs = 4.33x 10⁻⁴ yrs⁻¹
Half-Life => t(1/2) = (0.693/4.33 x 10⁻⁴)yrs⁻¹ = 1600 yrs.
