I need urgent help with this problem!

I have shown how far I got with it, but now I'm stuck, I dont know what to do next. Someone Please help me out.

∃xMxa & ∀x(Mxa →Kxa); ∀y(Kya → (y =b v y = c)) ∴ ¬Kba →Kca

1. ∃xMxa & ∀x(Mxa →Kxa) A

2. ∀y(Kya → (y =b v y = c)) A

3. Show ¬Kba →Kca

4. ¬Kba ACP

5. Mda & ∀x(Mxa →Kxa) ∃E, 1

6. Mda &E, 5

7. ∀x(Mxa →Kxa) &E, 5

8. Mda →Kda ∀E, 7

9. Kda →E, 6, 8

10. Kda → (d =b v d = c) ∀E, 2

11. (d =b v d = c) →E, 9, 10

12.