Question 6 (10 marks): Material costing $40 is used in a process to make one unit of product X. The material is in short supply and the company is unable to buy additional amount of the material from suppliers. Each unit of product X provides a contribution of $50 to the company. If we divert all the material required for making one unit of product X from product X to make one unit of product Y, what is the relevant cost of the material for making product Y for decision making purposes? (a) $10. (b) $50. (c) $90. (d) None of the above