How much of the parent isotope would be remaining after 7 half-lives have passed? a. 6.25 %
b. 1.56 %
c. 0.78 %
d. 0.39 %
If a radioactive element has a half-life of 425 years, how old would a rock be that only had 3.125 % of the parent isotope remaining?
a. 2125 years
b. 1700 years
c. 2550 years
d. 3400 years
Based on your graph above, approximately how much of the parent isotope would be remaining after 3.5 half-lives?
a. 16 %
b. 12 %
c. 4 %
d. 8 %
Based on your graph above, approximately how many half-lives have passed when only 35 % of the parent isotope is remaining?
a. 0.75
b. 1.5
c. 2.1
d. 2.5