<Tr> <Td> Strontium - 90 / yttrium - 90 </Td> <Td> β </Td> <Td> 28 years </Td> <Td> 30% </Td> <Td> </Td> </Tr> <Tr> <Td> Cesium - 137 </Td> <Td> β, γ </Td> <Td> 30 years </Td> <Td> 100% </Td> <Td> </Td> </Tr> <Tr> <Td> Promethium - 147 </Td> <Td> β </Td> <Td> 2.6 years </Td> <Td> 0.01% </Td> <Td> </Td> </Tr> <Tr> <Td> Cerium - 144 </Td> <Td> β, γ </Td> <Td> 285 days </Td> <Td> 0.01% </Td> <Td> </Td> </Tr>

List three radioactive elements and their products after nuclear decay