Respuesta :

Answer:

1 gm = 1000 mg

N = No e^-y t       where y = lambda the decay constant

N / N0 = .9969

ln .9969 = - y t

-.00310 = - 5 y

y = .00310 / 5 = .000621

So the half-life = .693 / y

T^1/2 = .693 / .000621 = 1116 or about 1120 yrs