CREATE TABLE table_62874 ("Model" TEXT, "Built" TEXT, "Quantity" FLOAT, "Seats" FLOAT, "Length" TEXT, "Engine" TEXT)

What is the Quantity of the engine Model PG-2901?
SELECT "Quantity" FROM table_62874 WHERE "Model" = 'pg-2901'
SELECT "Quantity" FROM "table_62874" WHERE "Model" = 'pg-2901'