Table: commuter_rail_vehicle_data
Columns: year_built
builder
model
fleet_id
seats

Question: Which model has 175 seats?
SQL: SELECT "model" FROM commuter_rail_vehicle_data WHERE "seats" = 175

Question: In what year was the ctc-3 model built?
SQL: SELECT "year_built" FROM commuter_rail_vehicle_data WHERE "model" = 'ctc-3'

Question: How many seats does the BTC-5 model have?
SQL: SELECT SUM("seats") FROM commuter_rail_vehicle_data WHERE "model" = 'btc-5'

Question: For the train built in 2012 with less than 179 seats, what is the Fleet ID?
SQL: SELECT "fleet_id" FROM commuter_rail_vehicle_data WHERE "year_built" = '2012' AND "seats" < 179