Question: How many in the introduced section had fokker as a manufacturer, a quantity of 5, and retired later than 1999?
SQL: SELECT SUM("Introduced") FROM "2-150761-1" WHERE "Manufacturer" = 'fokker' AND "Quantity" = 5.0 AND "Retired" > 1999.0;

Question: What is the total number of quantity when the introductory year was 1984?
SQL: SELECT SUM("Quantity") FROM "2-150761-1" WHERE "Introduced" = 1984.0;

Question: How many in the introduced segment retired later than 1994 and had fokker as a manufacturer?
SQL: SELECT COUNT("Introduced") FROM "2-150761-1" WHERE "Retired" > 1994.0 AND "Manufacturer" = 'fokker';

Question: How many in the quantity section had fokker as a manufacturer and retired later than 1999?
SQL: SELECT COUNT("Quantity") FROM "2-150761-1" WHERE "Manufacturer" = 'fokker' AND "Retired" > 1999.0;