Asked by Dena

I don't know the correct answer that's what i have to find.

for the first part here is my work.....
6.2e-4/min=0.0372seconds
half life: t_1/2=0.693/0.372s
=18.6sec*1min/60sec=0.310min (which is not right!)
Answered by DrBob222
See below.