user: Question: Tell me the payload that has an In service for 2011
Columns: ['Missile', 'Project', 'Type', 'Warhead', 'Payload (kg)', 'Range (km)', 'Dimension (m)', 'Fuel/Stages', 'Weight (kg)', 'In service']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Agni-I', 'IGMDP', 'Strategic', 'Nuclear, HE, penetration, sub-munitions, FAE', '1,000', '700–1,250', '15X1', 'Single stage solid', '12,000', '2002']
SQL:

assistant: SELECT "Payload (kg)" FROM "Table" WHERE "In service" = '2011';