A.S+X+T=Y+M+G B.S+I+(T-G)=M-X C.S+M+T=I+X+G D.S+(G-T)-I=(X-M)
A.MPC=0.7;MPM=0.2 B.MPC=0.3;MPM=0.2 C.MPC=0.8;MPM=0.2 D.MPC=0.5;MPM=0.2
A.S=-60+0.3Y B.S=-60+0.7Y C.S=40+0.3Y D.S=-40+0.3Y