Compute a $4-$period weighted moving average forecast

for period $6$ using a weight of $0\mathrm{.}3$ for the most recent

period, $0\mathrm{.}3$ for the next, $0\mathrm{.}2$ for the next, and $0\mathrm{.}2$ for the

next.period $1,2,3,4,5,6$ and demand is $41$ for $5$ period, $40$ for $4,43$ for $3,40$ for $2$ and $42$ for $1$ period