Refer to SFAS No. 157: Suppose a your company has investments in a wide array of assets, including (a) common stocks; (b) bonds; (c) real estate; (d) coal mine investments, which receive cash flows from sales of coal; (e) private equity funds; and (f) illiquid asset-backed securities. Consider how the portfolio manager would estimate the fair values of each of those classes of assets, and characterize the inputs you identify as Level 1, Level 2, or Level 3.