CREATE TABLE table_53303 ("D 50 O" TEXT, "D 49 \\u221a" TEXT, "D 48 \\u221a" TEXT, "D 47 \\u221a" TEXT, "D 46 \\u221a" TEXT, "D 45 \\u221a" TEXT, "D 44 \\u221a" TEXT, "D 43 \\u221a" TEXT, "D 42 \\u221a" TEXT, "D 41 \\u221a" TEXT)

Name the D 42 for when it has D 49 of r 12
SELECT "D 42 \u221a" FROM table_53303 WHERE "D 49 \u221a" = 'r 12'
SELECT "D 42 \u221a" FROM "table_53303" WHERE "D 49 \u221a" = 'r 12'