Copper(i) ions in aqueous solution react with nh3(aq) according to

The complete question is; copper (i) ions in aqueous solutions react with NH3(aq) according to;
 Cu +2NH3 = Cu(NH3)2    Kt= 6.3 × 10^10
Calculate K
Cu + 2NH3 = Cu(NH3)2
kf = 6.3 ×10^10
The ksp for CuBr = Cu + Br = 6.3 × 10^-9
For the reaction; CuBr +2NH3 = Cu(NH3)2 + Br to calculate K?
K = (6.3 × 10^10)(6.3×10^-9) 
Thus K is 396.9 

30litre of li2o is 1.0002mole approximately 1 mole