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Radioactive Strontium The half-life of strontium-90 is 28 years. How long will it take a 50- mg sample to decay to a mass of 32 mg?

The time taken is obtained as 3 years.What is the time taken?We know that radioactivity has to do with the fact that a substances does disintegrate gradually over a period of time.Let us recall the formula;N/No = (1/2)^t/t1/2N = The mass of radioactive atoms at time tNo = The mass of radioactive atoms initially presentt = time takent/12 = half life of the radioactive nucleusThen;32/50 = (1/2)^t/280.64 =  (1/2)^t/28log 0.64 = t/28 log0.5t/28 = log(0.64/0.5)t = 28 * log(0.64/0.5)t = 3 yearsLearn more about half life:https://brainly.com/question/24710827#SPJ1