user: Question: What date was an episode broadcasted on that had a run time of 24:40?
Columns: ['Episode', 'Broadcast date', 'Run time', 'Viewers (in millions)', 'Archive']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['" Episode One "', '26February1972', '24:40', '6.4', 'RSC converted (NTSC-to-PAL)']
SQL:

assistant: SELECT "Broadcast date" FROM "Table" WHERE "Run time" = '24:40';