(a)[2]
State what the term radioactive decay means.
(b)
Fig. 13.1 illustrates how the number $N$ of technetium-101 nuclei in a radioactive sample varies with time $t$.
(b(i))[4]
Use Fig. 13.1 to find the activity, in Bq, of the technetium-101 sample when $t = 14.0$ minutes. Show your working.
(b(ii))[2]
Without finding the half-life of technetium-101, use your answer in (i) to determine the decay constant $\lambda$ for technetium-101.