CREATE TABLE table_3171 ("Butter" TEXT, "Calories  ( 1 tbsp . ) " FLOAT, "Protein  ( g ) " TEXT, "Fat  ( g ) " TEXT, "Calcium  ( mg ) " TEXT, "Zinc  ( mg ) " TEXT)

Name the calcium for fat being 6.5
SELECT "Calcium (mg)" FROM table_3171 WHERE "Fat (g)" = '6.5'
SELECT "Calcium (mg)" FROM "table_3171" WHERE "Fat (g)" = '6.5'