user: Question: What is the used (kb) when the graphics mode is 4?
Columns: ['Graphics mode', 'Char cells', 'Pixels', 'Hardware colours', 'used (KB)', 'map', 'Type']
Types: ['real', 'text', 'text', 'real', 'real', 'text', 'text']
Sample row: [0.0, '80 × 32', '640 × 256', 2.0, 20.0, '3000–7FFF', 'Graphics']
SQL:

assistant: SELECT "used (KB)" FROM "Table" WHERE "Graphics mode" = 4.0;