Which of the following statements are correct?

A - if a project's NPV is less than zero, then its IRR must be less than the WACC

B - the lower the WACC used to calculate a project's NPV, the lower the calculated NPV will be

C - if a project's NPV s greater than zero, then its IRR must be less than zero

D - The NPV of a relatively low-risk project should be found using a relatively high WACC