The McDonald's fast$-$food restaurant on campus sells an average of $4,000$ quarter$-$pound hamburgers each week. Hamburger patties are resupplied twice a week, and on average the store has $350$ pounds of hamburger in stock. Assume that the hamburger patties cost $$1\mathrm{.}00$ a pound. What is the inventory turnover for the hamburger patties? On average, how many days of supply are on$-$hand?