Table: bakerloo_line
Columns: name
map_colour
first_operated
type
length
no_sta
current_stock
future_stock
trips_per_annum_1000
avg_trips_per_mile_1000

Question: When 4744 is the avg. trips per mile (x1000) what is the current stock?
SQL: SELECT "current_stock" FROM bakerloo_line WHERE "avg_trips_per_mile_1000" = 4744

Question: When green is the map colour what is the future stock?
SQL: SELECT "future_stock" FROM bakerloo_line WHERE "map_colour" = 'Green'

Question: When turquoise is the map colour how many avg. trips per mile (×1000)  are there?
SQL: SELECT COUNT("avg_trips_per_mile_1000") FROM bakerloo_line WHERE "map_colour" = 'Turquoise'

Question: When turquoise is the map colour what is the length?
SQL: SELECT "length" FROM bakerloo_line WHERE "map_colour" = 'Turquoise'