please show your work with the formula used

Hardchoice Corp. is a firm considering prospective capital budgeting projects. Selected data on the projects follow: 4. Consider only projects A and B by examining the incremental project cash flows BA. They are mutually exclusive opportunities. If the IRR RBA=12% and the discount rate is 15% then what is your decision? (A) Since IRR BA RRR then since the incremental project is a financed project, we should Accept Project B over A. (C) Since IRR RaA RRR then since the incremental project is an investment project, we should Accept Project B over A. (E) None of the above are true