Cobalt-60 has an atomic weight of 60.00 g/mol and a half-life
of 5.260 years. If you start with a 1.000 gram sample of the
isotope, how much time will pass before you have just 0.100
grams of the isotope left?
a 16.44 years
b 18.44 years
C 17.47 years
d 14.77 years