# Question: At present a radioactive beta source with a long half life

At present, a radioactive beta source with a long half-life has an activity of 20 mCi.

(a) What is the present decay rate in decays per second?

(b) Assuming that one beta particle is emitted per decay, how many are currently emitted per minute?

(a) What is the present decay rate in decays per second?

(b) Assuming that one beta particle is emitted per decay, how many are currently emitted per minute?

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