Do not simply write the result. Always show your calculation or give an explanation. Write legibly!1. The number of nuclei in a radioactive sample decreases to one fourth ( 25.0%) of the original number in9.00 hours. At the end of the 9 hours it contains 2.50x10¹0 undecayed nuclei. (a) What is the activity of thesample at this time? (b) What will be the activity of the sample after 6.00 more hours? (c) How much moretime (in addition to the 6.00 hours) must the nurse wait before she can administer it to the patient, if theactivity must not be greater than 1.6x10³ Bq? Be careful with the units!

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Answered: 1. The number of nuclei in a…

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