Sales of industrial vacuum cleaners at Larry Armstrong Supply Co$.$ over the past $13$ months are shown below:

Month Jan Feb Mar Apr May Jun Jul

Sales $11141610151711$

Month Aug Sep Oct Nov Dec Jan Feb

Sales $141712141611$

a$.$ Using a moving average with $4$ periods, determine the demand for vacuum cleaners for next February $=$

$13\mathrm{.}25$

b$.$ What is the MAD for the moving average forecast?

$2\mathrm{.}36$

c$.$ Using a weighted moving average with $4$ periods, determine the demand for vacuum cleaners for February. Use $4,3,2,$ and $1$ for the weights of the most recent, second most recent, third most recent, and fourth most recent, respectively. $=$

$[$ Select $]$

d$.$ What is the MAD for the weighted moving average forecast?

$[$ Select $]$

e$.$ Based on MAD, which is a better forecast?

$[$ Select $]$