Question For the project shown in the following table, calculate the internal rate of return. Then indicate, for the project, the maximum cost of capital that the firm could have and still find the IRR acceptable. What is the project's IRR?

I figured out the IRR is 6.88% using Excel. How do I calculate the "maximum cost of capital that the firm could have and still find the IRR acceptable?

Initial investment	$100,000
Year (t)	Cash inflows
1	$20,000
2	$35,000
3	$25,000
4	$30,000
5	$10,000