Which of the following statements is (are) true? i. if labor and capital are perfect substitutes in production, the isoquant is a downward-sloping line. ii. if a company needs to use inputs in fixed proportion such that the capital to labor ratio is always 2, the firm's isoquants are l-shaped. iii. if the production function is given by q = min(14, 7), the firm can produce, at minimum, 21 units of output.

Western electric has 32,000 shares of common stock outstanding at a price per share of $79 and a rate of return of 13.00 percent. the firm has 7,300 shares of 7.80 percent preferred stock outstanding at a price of $95.00 per share. the preferred stock has a par value of $100. the outstanding debt has a total face value of $404,000 and currently sells for 111 percent of face. the yield to maturity on the debt is 8.08 percent. what is the firm's weighted average cost of capital if the tax rate is 39 percent?