幾個organic chem問題

1. CH3 -CO-CH3 + Li(CH3)2 --> ?

2. how many possible structures of C4H8?

3. Reaction:

(Ar,Br連住個C)
Br-CH2-CH Ar Br + RR'R"COK
--> H-C(triple bonds)C-Ar + 2KBr + 2t-butanol


why use 3R-OK ,,not KOH? if use KOH,,what will be formed?