$(10)$ A company uses a $3-$month weighted moving average to forecast demand. The weights for the last $3$ months are $0\mathrm{.}4,0\mathrm{.}3,$ and $0\mathrm{.}3,$ respectively. The demand for the last $3$ months is $100,120,$ and $140$ units, respectively. What is the forecast for the next month?

$5$