Please Solve BY HAND not using Excel

Problem 4: Replacement McKain and Co. is currently manufacturing the plastic components of its product using a Thermoforming machine. The unit cost of the product is $16, and in the past year 4,000 units were produced and sold for $24 each. It is expected that the future demand of the product and the unit price will remain steady at 4,000 units per year and \$24 per unit, respectively. The company has two options: Option 1 - Keep the current Thermoforming machine: The machine has a remaining useful life of three years and could be sold on the open market now for $8,000. Three years from now, the machine is expected to have a salvage value of $1,800. Option 2 - Buy a New Machine: A new machine would cost $40,000, and the unit manufacturing cost on the new machine is projected to be $14. The new machine has an expected economic life of five years and an expected salvage value of $8,000. The appropriate MARR is 10%. The firm does not expect a significant improvement in the machine's technology to occur, and it needs the service of either machine for an indefinite period of time. Use the opportunity cost approach to solve the following. (a) Plot the cash flow diagram if the firm decides to retain the old machine. (b) Plot the cash flow diagram if the firm decides to purchase the machine. (c) Should the new machine be acquired now? Justify your answer Problem 4: Replacement McKain and Co. is currently manufacturing the plastic components of its product using a Thermoforming machine. The unit cost of the product is $16, and in the past year 4,000 units were produced and sold for $24 each. It is expected that the future demand of the product and the unit price will remain steady at 4,000 units per year and \$24 per unit, respectively. The company has two options: Option 1 - Keep the current Thermoforming machine: The machine has a remaining useful life of three years and could be sold on the open market now for $8,000. Three years from now, the machine is expected to have a salvage value of $1,800. Option 2 - Buy a New Machine: A new machine would cost $40,000, and the unit manufacturing cost on the new machine is projected to be $14. The new machine has an expected economic life of five years and an expected salvage value of $8,000. The appropriate MARR is 10%. The firm does not expect a significant improvement in the machine's technology to occur, and it needs the service of either machine for an indefinite period of time. Use the opportunity cost approach to solve the following. (a) Plot the cash flow diagram if the firm decides to retain the old machine. (b) Plot the cash flow diagram if the firm decides to purchase the machine. (c) Should the new machine be acquired now? Justify your