Respuesta :

taskmasters
Half life is determined using the equation expressed as:

A = Ao e^-kt

First, we need to find for the value k.

A = .67Ao = Ao e^-k(33 min)
k = 0.0121

The half-life is then calculated as follows:
A = .5Ao = Ao e^-0.0121(t)
t = 57.28 min