A business has recently purchased a tonne of PVC material at a cost of 350. The material could be sold immediately for 320 or it could be used as a substitute for another type of material that costs 310 per tonne. The PVC material is in continuous use within the business and its replacement cost is 360 per tonne. What is the relevant cost of the material? a. 350 O b. 360 O c. 320 O d. 630 e. 310