Question # $8$: A particular item has a demand of $9,000$ units per year. The cost of one procurement is SR$.100/-$ and the holding cost per unit is SR$.2\mathrm{.}40$ per year. The replacement is instantaneous and no shortages are allowed. Determine: $($a$)$ Economic lot size, $($b$)$ The number of orders per year, $($c$)$ The time between orders, and $($d$)$ the total cost per year if the cost of one units is Re$\mathrm{.}1/-$