Factor completely the following questions: Note: If a question cannot be factored, state "prime" or "non-factorable" and explain the reason why.

1) +421

2) 9+10

3) ++20

4) +56

5) 298

6) 1211+2

7) 3 8 +4

8) 9 + 42 15

9) 32 + 16 + 2