I have been working on this problem for a while now, and it's supposed to be really simple, but I can't get the solution can you sort of guide me through this problem, and show me the equations you used?
Problem: A radioactive sample containing 1.35 x 1017 nuclei has activity 2.57 x 1012 Bq.
A- What is this nuclide half-life?
Please keep answer short and simple and please no copy and paste.