ABC Co$.$ is to plan its workforce and production levels for next year. Forecast demands for the next $4$ quarters are $1160,960,1150,1380$ units. Ending inventor last year is expected to be $60,$ and the ABC would like to have a minimum of $50$ units in inventory at the end of next year. The cost of holding one unit in invento for one quarter is $$190.$ There are currently $200$ workers. The cost of hiring one worker is $$700,$ and the cost of firing one worker is $$1500.$ In the past, the plant manager observed that over $60$ workings days and with the workfor level constant at $200$ workers, ABC produced $1200$ units. The number of working days for the next $4$ quarters are respectively $61,62,65,$ and $58.$ Assume that ABC plans to adopt a level strategy $($constant workforce plan$)$ for next year. Determine the level of workforce for next year such that all quarterly demands will b met