Nuclear Physics
posted by amy .
An investigator receives Co60 (5.27 year half life) for use in a research study.
Unfortunately the Co60 is contaminated with Cs137 (30.0 year half life). The
initial Co60 activity is 400 times the initial Cs137 activity. How long after the
initial assay will the Cs137 activity be 0.2 times the Co60 activity?

Nuclear Physics 
Professor Waller
Stop using these discussion boards for your assignments..or I will find out who you are.

Nuclear Physics 
terry
Oh noes
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