The half-life of cobalt-60 is 5.3 years. How many years will it take for 1/4 of the original amount of coblat-60 to remain?
It this not TWO half-lives.....?
And if a half-life is
How long until
The half-life equation is :
What we know:
#A(t)->"Amount left after t years"=1/4 A_0#
Substituting in the equation:
Dividend both sides by