A.2.1×(P/F,12%,1)+2205×(P/F,12%,2)+22.05×(1+2%)×(P/F,12%,2)
B.2.l/(12%-5%)+22.05X(1+2%)(P/F,12%,2)
C.21×(P/F,12%,1)+2.205×(P/F,12%,2)+2205×(1+2%)×(P/F,12%,3)
D.2.l/(12%-5%)+22.05×(1+2%)(P/F,12%,3)