Consider the Following Demand and Forecast If MAD = 2 for the Four Periods Under Consideration

Multiple Choice

Consider the following demand and forecast.
$$\begin{array} { | c | c | c | } \hline \text { Period } & \text { Demand } & \text { Forecast } \\\hline 1 & 7 & 10 \\\hline 2 & 12 & 15 \\\hline 3 & 18 & 20 \\\hline 4 & 22 & \\\hline\end{array}$$
If MAD = 2 for the four periods under consideration, what is the forecast for period 4?

A) 19
B) 20
C) 21
D) 22