c. Finding each project's IRR (Using the Excel IRR function, set the guess parameter to be 10%.) IRR d. Finding the crossover rate (Using the Excel IRR function, set the guess parameter to be 10%.) c. Finding each project's IRR (Using the Excel IRR function, set the guess parameter to be 10%.) IRR d. Finding the crossover rate (Using the Excel IRR function, set the guess parameter to be 10%.)