user: Question: What is the decimal value when the memory map and byte string are standard, and the max memory is 512?
Columns: ['Model', 'Floating point', 'Decimal', 'Byte string', 'Memory map', 'Max memory (kwords)']
Types: ['text', 'text', 'text', 'text', 'text', 'real']
Sample row: ['Sigma 7', 'optional', 'optional', 'standard', 'optional', 128.0]
SQL:

assistant: SELECT "Decimal" FROM "Table" WHERE "Byte string" = 'standard' AND "Memory map" = 'standard' AND "Max memory (kwords)" = 512.0;