For Questions 18 and 19: A new school is to be built in a newly developed community. Three contactors submitted their proposals as follows: Proposal Annual Benefits. million SR X 19.80 26.00 Z 29.00 Annual Costs, million SR 17. 60 5 21.70 28.00 Annual Disbenefits. million SR .00 Annual Savings million SR 6.00 17.00 10.00 9.00 18. Proposals ranking based on their individual B C from best to worst is: a) Y, Z, X b) X,Z,Y OY.XZ d) X,Y,Z 19. Proposals ranking based on individual B-C from best to worst is: a) X,Z,Y b) YXZ OYZ, X X Y Z