Incremental ROR

please help

There are 5 alternatives to be considered: a1, a2, a3, a4 and a5 with the corresponding investment of $500 respectively. If MARR = 12%, find the best alternative based upon the calculated incrmental rate of return table presented below. Clearly show your logical comparison and reason of your conclulation There are 5 alternatives to be considered: a1, a2, a3, a4 and a5 with the corresponding investment of $500 respectively. If MARR = 12%, find the best alternative based upon the calculated incrmental rate of return table presented below. Clearly show your logical comparison and reason of your conclulation