Your firm is considering issuing one-year debt and has come up with the following estimates of the value of the interest tax shield and the probability of distress for different levels of debt: Suppose the firm has a beta of zero, so that the appropriate discount rate for financial distress costs is the risk-free rate of 5%. Which level of debt above is optimal if, in the event of distress, the firm will have distress costs equal to $2 million? $80 million $90 million $50 million $2 million