Solve the all parts of given question:
Question: The radioactive source in most smoke detectors is 241Am, which has a half-life of 432 years. Suppose only about 6.50×102 mg of this material is needed.
Part A: What is the initial source activity?
Part B: What would be the source's activity after 50 years in operation?
Part C: How many 241Am, nuclei would have decayed in this 50-year period?
I don't understand how to get the answer. Can you please help me with this question, Please help?