CREATE TABLE table_51481 ("Driver" CLOB, "Constructor" CLOB, "Laps" FLOAT, "Time/Retired" CLOB, "Grid" FLOAT)

How many laps were there when time/retired was gearbox?
SELECT SUM("Laps") FROM table_51481 WHERE "Time/Retired" = 'gearbox'
SELECT SUM("Laps") FROM "table_51481" WHERE "Time/Retired" = 'gearbox'