$4,000$ units per month. The setup cost for production is $$250,$ and the holding cost is $$20$ per chair per year. The production rate is $800$ chairs per day. Assume $30$ working days per month. Determine the following:

a$)$ D $($annual demand$),$ S$,$ H$,$ p$,$ u

b$)$ EPQ

c$)$ Run time