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.