please answer a and b

WACC_-Market value weights The market values and after-tax costs of various sources of capital used by Ridge Tool are shown in the following table: a. Calculate the firm's weighted average cost of capital. b. Explain how the firm can use this cost in the investment decision-making process. a. The firm's weighted average cost of capital, ra, using market value weights is \%. (Round to two decimal places.) Data table (Click on the icon here in order to copy the contents of the data table below into a spreadsheet.)