CREATE TABLE table_78139 ("D 41 O" TEXT, "D 42 O" TEXT, "D 43 O" TEXT, "D 44 O" TEXT, "D 45 +" TEXT, "R 55 +" TEXT, "R 54 +" TEXT, "R 53 +" TEXT, "R 52 O" TEXT, "R 51 O" TEXT)

What is the value of D 42 O that has an R 53 + value of r 8?
SELECT "D 42 O" FROM table_78139 WHERE "R 53 +" = 'r 8'
SELECT "D 42 O" FROM "table_78139" WHERE "R 53 +" = 'r 8'