<Tr> <Th> Natural abundance </Th> <Td> 98.93% </Td> </Tr> <Tr> <Th> Parent isotopes </Th> <Td> </Td> </Tr> <Tr> <Th> Isotope mass </Th> <Td> 12 u </Td> </Tr> <Tr> <Th> Spin </Th> <Td> 0 </Td> </Tr>

List the mass number atomic number of carbon-12 and carbon-13 respectively