user: Question: What band is the highest and has a System of GSM-450?
Columns: ['System', 'Band', 'Uplink (MHz)', 'Downlink (MHz)', 'Channel number']
Types: ['text', 'real', 'text', 'text', 'text']
Sample row: ['T-GSM-380', 380.0, '380.2–389.8', '390.2–399.8', 'dynamic']
SQL:

assistant: SELECT MAX("Band") FROM "Table" WHERE "System" = 'GSM-450';