Which statement about radioactive decay is correct?
The rate of decay of a radioactive sample can be decreased by cooling it to a very low temperature.
It is impossible to predict which specific nucleus in a sample will decay next.
The half-life of a radioactive isotope depends on the initial number of undecayed nuclei.
A radioactive sample decays completely to zero activity after exactly two half-lives.
120 exam-style questions on CIE IGCSE Physics 5.2.3a Radioactive decay. Each one has a worked solution and a mark scheme showing where the marks go.