Answer:
N = 32 atoms
Explanation:
The radioactive elements decays as follows:
Ln (N/N₀) = -kt
Where N are number of atoms after t time, N₀ are initial number of atoms, k is decay constant in time⁻¹
We can obtain k from t(1/2):
k = ln 2 / t(1/2)
k = 0.02236s⁻¹
Ln (N/128 atoms) = -0.02236s⁻¹*62s
(N/128 atoms) = e^-1.386
N/128 atoms = 0.25
N = 128 atoms * 0.25
N = 32 atoms
