Sales in four consecutive months are 100, 200, 250 and 300 units respectively. In these same four months, the corresponding f beginning of the months were 80, 220, 170 and 180 units respectively. What is the accuracy of the forecast over the 4-month p measure? (Assume % is based on the sales) a. 60 units
b. 28%
c. 37%
d. none of the above