user: Question: What is Fastest Lap, when Date is Leeds, Alabama, and when Circuit is April 19?
Columns: ['Circuit', 'Location', 'Date', 'Pole Position', 'Fastest Lap', 'Winner']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['March 8', 'Daytona International Speedway', 'Daytona Beach, Florida', 'Mat Mladin', 'Mat Mladin', 'Mat Mladin']
SQL:

assistant: SELECT "Fastest Lap" FROM "Table" WHERE "Date" = 'Leeds, Alabama' AND "Circuit" = 'April 19';