CREATE TABLE table_202_82 (id DECIMAL, "weapon name" TEXT, "caliber  ( mm ) " TEXT, "range  ( max ) " TEXT, "warhead" TEXT)

which three weapons have the highest caliber ?
SELECT "weapon name" FROM table_202_82 ORDER BY "caliber (mm)" DESC LIMIT 3
SELECT "weapon name" FROM "table_202_82" ORDER BY "caliber (mm)" DESC NULLS LAST LIMIT 3