From the calculations, we can see that the half life of the material is 11.4 days
The term radioactivity refers to the spontaneous disintegration of a radioactive nucleus. The time taken for half of the radioactive material to remain.
Given that;
N/No = (1/2)^t/t1/2
N = amount that remained
No = amount that remained in the beginning
t = time taken
t1/2 = half life of the substance
N =Noe^-kt
4.995 ×10^9 = 1.75 x 10^12e^-55k
3.5* 10-2=e^-55k
k = ln3.5* 10-2/-55
k =0.06095
t1/2 = 0.693/0.06095
t1/2 = 11.4 days
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