B) 8 → 20, 2 → 5, 10 → 25, 4 → ?
C) 11 → 3, 35 → 9, 3 → 1, 19 → ?
D) 6 → 1, 9 → 7, 3 → -5, 8 → ?
E) 6 → 9, 8 → 15, 4 → 3, 10 → ?