Average demand for a particular item is $1,200$ units per year. it costs $$100$ to place an order for this item, and it costs $$6$ to hold one unit of this item In invertory for one year. If the fixed$-$order$-$nterval model is chosen in this instance, how often $($on average$)$ will this item be ordered?

Multple Cholce

once a month

once every other month

twice a month

once every three months

three times every two months