Please answer in detailed steps

Exercise 5.5. Assume a 2 -by-2 economy with the state space ={1,2} and two contingent assets with prices St1 and St2,t{0,T}. Assume S01>0 and S02>0. Let STi(j)=S0iRji for some positive constants Rji,i,j=1,2. (a) Derive a simple condition (in terms of Rji ) for the completeness of this market model. (b) Determine the risk-neutral probabilities p~=P(1) and 1p~=P(2) such that the discounted price process St1St2 is a martingale, i.e. E[ST1ST2]=S01S02. (c) Assume that the market is complete (i.e., the condition derived in (a) holds). Determine the portfolio (1,2) that replicates an arbitrary payoff X. Obtain the formula for 0(X)