It really helps to fully know the 19 rules of inference.
1. (G * P) -> K
2. E -> Z
3. ~P -> ~Z
4. G ->(E v L) :. (G * ~L) -> K
--------------------------------
5. ~~Z -> ~~P 3 Transposition
6. Z -> P 5 Double Negation
7. E -> P 2,6 Hypothetical Syllogism
8. (P * G) -> K 1 Commutation
9. P -> (G -> K) 8 Exportation
10. E -> (G -> K) 7,9 Hypothetical Syllogism
11. ~G v (E v L) 4 Material Implication
12. (~G v E) v L 11 Association
13. (E v ~G) v L 12 Commutation
14. (~~E v ~G) v L 13 Double Negation
15. ~(~E * G) v L 14 De Morgan's Law
16. (~E * G) -> L 15 Material Implication
17. ~E -> (G -> L) 16 Exportation
18. ~(G -> L) -> ~~E 17 Transposition
19. ~(G -> L) -> E 18 Double Negation
20. ~(G -> L) -> (G -> K) 19,10 Hypothetical Syllogism
21. (G -> L) v (G -> K) 20 Material Implication
22. (~G v L) v (~G v K) 21 Material Implication
23. ~G v (L v ~G) v K 22 Association
24. ~G v (~G v L) v K 23 Commutation
25. (~G v ~G) v (L v K) 24 Association
26. ~G v (L v K) 25 Tautology
27. (~G v L) v K 26 Association
28. (~G v ~~L) v K 27 Double Negation
29. ~(G * ~L) v K 28 De Morgan's Law
30. (G * ~L) -> K 29 Material Implication