<Tr> <Td> O </Td> <Td> 8 </Td> <Td> </Td> <Td> 12.034405 (20) </Td> <Td> 580 (30) × 10 s (0.40 (25) MeV) </Td> <Td> 2p (60.0%) </Td> <Td> </Td> <Td> 0 + </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> p (40.0%) </Td> <Td> </Td> </Tr> <Tr> <Td> O </Td> <Td> 8 </Td> <Td> 5 </Td> <Td> 13.024812 (10) </Td> <Td> 8.58 (5) ms </Td> <Td> β (89.1%) </Td> <Td> </Td> <Td> (3 / 2 −) </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> β, p (10.9%) </Td> <Td> </Td> </Tr>

What is the mass number of an oxygen isotope that has nine neutrons