The Monthly Sales for SJB Pipes Inc A) Plot the Monthly Sales Data on a Sheet of \begin{array}

The monthly sales for SJB Pipes Inc. were as follows:
$$\begin{array} { | c | c | } \hline \text { Month } & \text { Sales } \\\hline \text { January } & 20 \\\hline \text { February } & 21 \\\hline \text { March } & 15 \\\hline \text { April } & 14 \\\hline \text { May } & 13 \\\hline \text { June } & 16 \\\hline \text { July } & 17 \\\hline \text { August } & 18 \\\hline \text { September } & 20 \\\hline \text { October } & 20 \\\hline \text { November } & 21 \\\hline \text { December } & 23 \\\hline\end{array}$$ A) Plot the monthly sales data on a sheet of paper.
B) Forecast January sales using each of the following:
1) naïve method
2) 3-month moving average.
3) 6-month weighted average using 0.1, 0.1, 0.1, 0.2, 0.2, and 0.3 with the heaviest weights for recent months
4) exponential smoothing using α = 0.3 and a September forecast of 18.
5) a trend projection
C) With the data given, which method would allow you to forecast sales for next March?