A company must meet the following demands for

a product: January, $30$ units; February, $30$ units; March,

$20$ units. Demand may be backlogged at a cost of

$$5/$unit$/$month$.$ All demand must be met by the end of March.

Thus, if $1$ unit of January demand is met during March, a

backlogging cost of $5(2)$ $$10$ is incurred. Monthly

production capacity and unit production cost during each

month are given in Table $66.$ A holding cost of $$20/$unit is

assessed on the inventory at the end of each month.