A firm is trying to decide which of two devices to install to reduce costs in a particular situation Devices A costs $1000, device B costs $1350 and both have useful lives of 5 years and no salvage value Device A can be expected to result in $300 savings annually Device B will provide cost savings of $300 the first year, but savings will increase by $50 annually, making the second-year savings $350, the third-year savings $400, and so forth With interest rate at 7%, which device should the firm purchase? Use Cost Benefit Ratio to solve this question. Show all your steps, build models, provide them with number, come up with results and show their units, then, draw conclusions.