<Tr> <Td> 50! North America </Td> <Td> Nicaragua </Td> <Td> Pacific Ocean </Td> <Td> Caribbean Sea </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> isthmus - canal! Nicaragua Canal (proposed) </Td> </Tr> <Tr> <Td> 50! North America </Td> <Td> Costa Rica </Td> <Td> Pacific Ocean </Td> <Td> Caribbean Sea </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 55! North America & South America </Td> <Td> Panama </Td> <Td> Gulf of Panama </Td> <Td> Caribbean Sea </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> isthmus - canal! Panama Canal </Td> </Tr> <Tr> <Td> 60! South America </Td> <Td> Colombia </Td> <Td> Pacific Ocean </Td> <Td> Caribbean Sea </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> </Td> </Tr>

How many african countries have the atlantic ocean for their southern boundary