What is highlighted in red has specific instructions. P1-4 the answer I did is correct it needs to be though excel formula. Just go by the breakdown on how I got the answer. p1-8 need a grid drawn....

P1-4
    P1–4 Marginal cost–benefit analysis and the goal of the firm Ken Allen, capital budgeting analyst for Bally Gears, Inc., has been asked to evaluate a proposal. The manager of the automotive division believes that replacing the robotics used on the heavy truck gear line will produce total benefits of $560,000 (in today’s dollars) over the next 5 years. The existing robotics would produce benefits of $400,000 (also in today’s dollars) over that same period. An initial cash investment of $220,000 would be required to install the new equipment. The manager estimates that the existing robotics can be sold for $70,000. Show how Ken will apply marginal cost–benefit analysis techniques to determine the following:
    a.       The marginal (added) benefits of the proposed new robotics.
    b.      The marginal (added) costs of the proposed new robotics.
    c.       The net benefit of the proposed new robotics.
    d.      What should Ken recommend that the company do? Why?
    e.       What factors besides the costs and benefits should be considered before the final decision is made?
                        QUESTIONS IN RED USE THE EXCEL FORMULA
     Answer
    a. The marginal (added) benefits of the proposed new robotics
    Marginal benefits are additional benefits                Benefits every year with new robotics    $560,000
    Benefits every year with new robotics = $560,000 per year                Less: Benefits every year with old robotics    $400,000
    Less: Benefits every year with old robotics = $400,000 per year                Marginal benefit per year    $160,000
    Thus Marginal (added) Benefits = $160,000 for 5 years = $800,000                Total marginal benefit for 5 years    $800,000
    b. The marginal (added) cost of the proposed new robotics.
    Marginal added cost will be additional cost
    Cost of new robotics = $220,000                Cost of new robotics    $220,000
    Less: Resale price of old robotics = $70,000                Less: Resale price of old robotics    $70,000
    Marginal added cost = $150,000                Marginal added cost     $150,000
    c. The net benefit of the proposed new robotics
    The net benefit of the proposed new robotics = Marginal (added) Benefits $800,000 - Marginal added cost $150,000 = $650,000                The net benefit of the proposed new robotics    $650,000
    d. The company shall get the new robotics as there is net benefit of $650,000, and future benefits are more than current benefits.
    e. Besides the costs and benefits the company shall consider the following factors also:
    Time value of money,
    Employees Training cost if required for new robotics.
    Employees behavior towards this installation.
    Environmental effects of such robotics, installed.
P1-8
    P1–8 Marginal tax rates Using the tax rate schedule given in Table 1.2, perform the following:
    a.       Find the marginal tax rate for the following levels of sole proprietorship earnings before taxes: $15,000; $60,000; $90,000; $150,000; $250,000; $450,000; and $1 million.
    b.       Plot the marginal tax rates (measured on the y-axis) against the pretax income levels (measured on the x-axis). Explain the relationship between these variables.
    ANSWER
    a.
    Taxable income = $ 15,000
    Since 15,000 is in the second slab i.e. pretax income is less than $ 38,700 marginal tax rate = 12%
    Taxable income = $ 60,000
    Since 60,000 is in the third slab i.e. pretax income is less than $ 82,500 marginal tax rate = 22%
    Taxable income = $ 90,000
    Since 90,000 is in the fourth slab i.e. pretax income is less than $ 157,500 marginal tax rate = 24%
    Taxable income = $ 150,000
    Since 150,000 is in the fourth slab i.e. pretax income is less than $ 157,500 marginal tax rate = 24%
    Taxable income = $ 250,000
    Since 250,000 is in the sixth slab i.e. pretax income is less than $ 500,000 marginal tax rate = 35%
    Taxable income = $ 450,000
    Since 450,000 is in the sixth slab i.e. pretax income is less than $ 500,000 marginal tax rate = 35%
    Taxable income = $ 1,000,000
    Since 1,000,000 is in the final slab i.e. pretax income is greater than $ 500,000 marginal tax rate = 37%
    The summary is shown in table below:
    Pretax income    Marginal tax rate
    15,000    12%
    60,000    22%
    90,000    24%
    150,000    24%
    250,000    35%
    450,000    35%
    1,000,000    37%
    b.                    NEED TO MAKE A GRID
     Marginal tax rate increases as level of pretax income increases. The rate of increase (slope of the curve) is high initially and decreases subsequently. Marginal tax rate becomes constant at 37% once pretax income exceeds $ 500,000.
Marginal tax rate
Marginal tax...