Consider the following history of supply and demand for new toasters from Valles Global: umber of Items Receive emand During the Month 520 1640 670 425 280 550 ont January 200 February 175 75 arc April May June 950 500 2050 . Determine the ending inventory each month. Assume excess demands are back-ordered and starting inventory on 1 January is 480 . Assume that each time a unit is demanded that cannot be supplied immediately, a one-time charge of 10 dollars is made. Determine the stock-out cost incurred during the six months if on-hand stocks exceed demand at the end of the month (requiring back-order) Suppose that each stock-out costs 10 dollars that the demand remains unfilled. If demands are filled on a first-come, first-served basis, what is the total stock-out cost incurred during the six months using this criterion? Discuss under what circumstances the cost criterion used in part 2 might be appropriate and under what circumstances part three may be more