<Tr> <Th_colspan="3"> ↓ Period </Th> </Tr> <Tr> <Th> </Th> <Td> </Td> <Td_colspan="17"> </Td> <Td> He </Td> </Tr> <Tr> <Th> </Th> <Td> Li </Td> <Td> Be </Td> <Td_colspan="11"> </Td> <Td> 5 </Td> <Td> 6 </Td> <Td> 7 </Td> <Td> 8 O </Td> <Td> 9 </Td> <Td> 10 Ne </Td> </Tr> <Tr> <Th> </Th> <Td> 11 Na </Td> <Td> 12 Mg </Td> <Td_colspan="11"> </Td> <Td> 13 Al </Td> <Td> 14 Si </Td> <Td> 15 </Td> <Td> 16 </Td> <Td> 17 Cl </Td> <Td> 18 Ar </Td> </Tr>

Where are the s p d and f blocks located