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Under an existing process, a part is machined from brass; however, testing has indicated that all desired properties for the part can be achieved with an injection molded high-density polyethylene part

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Under an existing process, a part is machined from brass; however, testing has indicated that all desired properties for the part can be achieved with an injection molded high-density polyethylene part. a. The current process uses a 2 in length of brass bar stock, which is cut from a longer piece costing$34/foot. The blank is then machined in a process taking6 min, and the shop rate is$75/hr. No additional equipment or tooling is required to keep doing the process the old way. You currently have a machine operator working full-time (7.5 hrs/day) to meet the daily requirements of 75 parts. b. The proposed process will use50 gof plastic per part, with a raw material cost of$3.70/kg. The injection molding shop charges a shop rate of$150/hr, and the cycle time is 30 s. The mold contains 6 cavities, and will cost$18,000to make. It has a lifespan of 100,000 cycles. Find the cost per part under each process. Then, perform an optimization calculation to determine the quantity at which the per-part cost of injection molding becomes more economical. Finally, determine the payback period - how many days will it take to recover the cost of the investment