Table: railroad_vehicles
Columns: number
builder
type
date
works_number

Question: Name the builder for number 3
SQL: SELECT "builder" FROM railroad_vehicles WHERE "number" = 3

Question: Name the date with works number less than 1673 and number less than 3
SQL: SELECT "date" FROM railroad_vehicles WHERE "works_number" < 1673 AND "number" < 3

Question: Name the builder for 4/1906 and works number more than 199
SQL: SELECT "builder" FROM railroad_vehicles WHERE "works_number" > 199 AND "date" = '4/1906'