Please explain the excel work. That's where I am struggling.

Direct labor, materials, selling expenses, and other variable costs are forecast to be $5.20, $3.70, $2.30, and $0.80, respectively in year 1 and grow with inflation. Lease payment, property taxes, administration, advertising, and other cash fixed costs are expected to be $4,100, $730, $680, $1,120, and $730, respectively in year 1 and grow with inflation. What are the Total Variable Cost per Unit and Total Cash Fixed Costs? Step 2: Consider the same problem as in Part II, but make the following modifications: Suppose we additionally assume that the project will require working capital in the amount of $1.23 in year 0 for every unit we expect to sell in year 1. Further, working capital needs will grow with inflation going forward. What is the project NPV? Step 3: Consider the same problem as in Part III. Assume that the product life-cycle of seven years is a reasonable bet, but you are concerned about the real demand for your product. This is a fairly new product, and demand may be more or less than your sales team believes. Further, if this (and other) risky projects take longer than expected, the firm's cost of capital may increase (because you are a riskier' borrower to your creditors). Analyze the sensitivity of your project (NPV) to the unit sales factor and to the cost of capital. Draw some conclusions about the project given your sensitivity analysis. Your boss wants to know whether it's a go or not, why you think so, and about which assumptions you are most concerned. Please explain. Direct labor, materials, selling expenses, and other variable costs are forecast to be $5.20, $3.70, $2.30, and $0.80, respectively in year 1 and grow with inflation. Lease payment, property taxes, administration, advertising, and other cash fixed costs are expected to be $4,100, $730, $680, $1,120, and $730, respectively in year 1 and grow with inflation. What are the Total Variable Cost per Unit and Total Cash Fixed Costs? Step 2: Consider the same problem as in Part II, but make the following modifications: Suppose we additionally assume that the project will require working capital in the amount of $1.23 in year 0 for every unit we expect to sell in year 1. Further, working capital needs will grow with inflation going forward. What is the project NPV? Step 3: Consider the same problem as in Part III. Assume that the product life-cycle of seven years is a reasonable bet, but you are concerned about the real demand for your product. This is a fairly new product, and demand may be more or less than your sales team believes. Further, if this (and other) risky projects take longer than expected, the firm's cost of capital may increase (because you are a riskier' borrower to your creditors). Analyze the sensitivity of your project (NPV) to the unit sales factor and to the cost of capital. Draw some conclusions about the project given your sensitivity analysis. Your boss wants to know whether it's a go or not, why you think so, and about which assumptions you are most concerned. Please explain