Your newest project has a 5545 debt to equity mix of capital for investment. What is the maximum cost of debt capital that will give you a WACC of 12 percent? The cost of equity capital is 5%. a) Define a variable x that is necessary to solve the problem (1 point) and state what the variable x represents. (2 points) b) Write an equation for the WACC in terms of the variable x. (5 points) c) Solve for x from the equation in part b above. (1 point) Specify the units for x. (1 point)