PLEASE HELP WITH EXCEL IF POSSIBLE - THANK YOU!!

Question 4) Calculate FV of an annuity (received) if: Monthly PMT on last day of each month =$1,250;r=9%;n=30 years Calculate FV of an annuity due if: Monthly PMT on first day of each month =$1,250;r=9%;n=30 years Why are the signs different? Can excel keep track of directionality of cashflow for you