Q. The 16 overhead doors on your loading dock must be replaced now. The deluxe model costs $2,200 each also will last for six yrs. The criterion model costs $1600 each also will last for four yrs. The deluxe model is aluminium, so it will have a scrap value. The use of the deluxe model on the loading dock will also save your organization $1000 per yr in heating costs because of its ability to seal better. If you use a mar of 12percent also present worth analysis, which door will you suggest?