A hospital records the number of floral deliveries its patients receive each day. For a two-week period, the records show 15, 27, 26, 24, 18, 21, 26, 19, 15, 28, 25, 26, 17, 23

The forecast for the period 15 using a four-period moving average to forecast is:

a.

22.75

b.

23.00

c.

22.14

d.

23.80