Evaluate each expression. 9. ⎪31⎥ + ⎪–5⎥10. ⎪–16⎥ – ⎪4⎥ 11. ⎪–28⎥ – ⎪–1⎥12. ⎪11–2⎥ 13. ⎪44⎥ + ⎪–34⎥14. ⎪–101⎥ – ⎪–1⎥