<Table> <Tr> <Th_colspan="2"> Cumulonimbus Cloud </Th> </Tr> <Tr> <Td_colspan="2"> Cumulonimbus' </Td> </Tr> <Tr> <Th> Abbreviation </Th> <Td> Cb </Td> </Tr> <Tr> <Th> Symbol </Th> <Td> </Td> </Tr> <Tr> <Th> Genus </Th> <Td> Cumulonimbus (heaped, rain) </Td> </Tr> <Tr> <Th> Altitude </Th> <Td> 460--7,620--12,190 m (1,500--25,000 - 65,000 ft) </Td> </Tr> <Tr> <Th> Appearance </Th> <Td> Very tall and large clouds </Td> </Tr> <Tr> <Th> Precipitation cloud? </Th> <Td> Yes, often intense </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Cumulonimbus Cloud </Th> </Tr>

Where do cumulonimbus clouds form in the atmosphere
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