Answer:
Coefficient
Explanation:
I am not that sure, but just wanted to help.
If the half life is 5 days, you would have to divide 222 by 2 3 times.
so 222/2 =111g
111/2 = 55.5g
55.5/2 = 27.75g
after four half life the mass would be
27.75/2
13.875g
the percent would be
13.875/222
= 6.25%