<Tr> <Td> 8 </Td> <Td> Argentina (ARG) </Td> <Td> 0 </Td> <Td> 0 </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> </Td> <Td> Grand Total </Td> <Td> 5 </Td> <Td> 5 </Td> <Td> 5 </Td> <Td> 15 </Td> </Tr> <Table> <Tr> <Th> Event </Th> <Th_colspan="1"> Gold </Th> <Th_colspan="1"> Silver </Th> <Th_colspan="1"> Bronze </Th> </Tr> <Tr> <Td> Men's singles details </Td> <Td> Andy Murray Great Britain </Td> <Td> Roger Federer Switzerland </Td> <Td> Juan Martín del Potro Argentina </Td> </Tr> <Tr> <Td> Men's doubles details </Td> <Td> Bob Bryan and Mike Bryan (USA) </Td> <Td> Michaël Llodra and Jo - Wilfried Tsonga (FRA) </Td> <Td> Julien Benneteau and Richard Gasquet (FRA) </Td> </Tr> <Tr> <Td> Women's singles details </Td> <Td> Serena Williams United States </Td> <Td> Maria Sharapova Russia </Td> <Td> Victoria Azarenka Belarus </Td> </Tr> <Tr> <Td> Women's doubles details </Td> <Td> Serena Williams and Venus Williams (USA) </Td> <Td> Andrea Hlaváčková and Lucie Hradecká (CZE) </Td> <Td> Maria Kirilenko and Nadia Petrova (RUS) </Td> </Tr> <Tr> <Td> Mixed doubles details </Td> <Td> Victoria Azarenka and Max Mirnyi (BLR) </Td> <Td> Laura Robson and Andy Murray (GBR) </Td> <Td> Lisa Raymond and Mike Bryan (USA) </Td> </Tr> </Table> <Tr> <Th> Event </Th> <Th_colspan="1"> Gold </Th> <Th_colspan="1"> Silver </Th> <Th_colspan="1"> Bronze </Th> </Tr>

Who won gold medal for tennis in olympic 2012
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