How would each of the following scenarios affect a firm’s cost of debt after tax, rd(1 - T); its cost of equity, rs; and its Weighted Average Cost of Capital (WACC)? Indicate with a plus (+), a minus (-), or a zero (0) whether the factor would raise, lower, or have no or an indeterminate effect on the item in question

How would each of the following scenarios affect a firm’s cost of debt after tax, r_d(1 - T); its cost of equity, r_s; and its Weighted Average Cost of Capital (WACC)? Indicate with a plus (+), a minus (-), or a zero (0) whether the factor would raise, lower, or have no or an indeterminate effect on the item in question. (Assume for each answer that other things are held constant.)

                                                                                   r_d(1 - T)            r_s                     WACC

a. The corporate tax rate is lowered.                        _____              _____              _____

b. Investors become more risk-averse.                    _____              _____              _____

c. Interest rates decline.                                           _____              _____              _____