user: Question: What is Heat, when Mark is 6.69?
Columns: ['Heat', 'Lane', 'Name', 'Country', 'Mark', 'React']
Types: ['real', 'real', 'text', 'text', 'text', 'real']
Sample row: [1.0, 6.0, 'Dwain Chambers', 'United Kingdom', '6.55 PB', 0.16]
SQL:

assistant: SELECT "Heat" FROM "Table" WHERE "Mark" = '6.69';