<Tr> <Td> 1993 </Td> <Td> Excel 5 </Td> <Td> Old version, no longer supported: 5.0 </Td> <Td> Included Visual Basic for Applications (VBA) and various object - oriented options </Td> </Tr> <Tr> <Td> 1995 </Td> <Td> Excel 95 </Td> <Td> Old version, no longer supported: 7.0 </Td> <Td> Renumbered for contemporary Word version . Both programs were packaged in Microsoft Office by this time . </Td> </Tr> <Tr> <Td> </Td> <Td> Excel 97 </Td> <Td> Old version, no longer supported: 8.0 </Td> <Td> </Td> </Tr> <Tr> <Td> 2000 </Td> <Td> Excel 2000 </Td> <Td> Old version, no longer supported: 9.0 </Td> <Td> Part of Microsoft Office 2000, which was itself part of Windows Millennium (also known as "Windows ME"). </Td> </Tr>

Explain how you can achieve security in an excel worksheet