Demand over the next four months are $450,500,350,$ and $400$ respectively. Regular time production costs $$10$ per item, and we can make a maximum of $400$ items in a given month in regular time. Overtime production costs $$16$ per item, and as many as $200$ items may be produced in overtime each month $($in addition to the regular time production$).$

Keeping an item in inventory incurs a cost of $$1$ per period; backorders cost $$3$ per period per item.

If we follow a level strategy of production, what would be the production quantity each month?