At the onset of Fall, Evergreen, a home decor retailer, is deciding on the quantity of "Winter Wonderland" candles to order for the winter season. Evergreen has a single opportunity to order these candles at their standard cost of $15 per candle, ensuring they are available to sell to customers during the winter. If Evergreen runs out of these candles during the season, it can place a rush order with the same supplier, albeit at a higher cost per candle. Evergreen sells the Winter Wonderland candles at a retail price of $50, regardless of whether the candle was purchased at the standard or rush price. Any candles remaining after the winter season are discounted to $10 to clear inventory. Assuming the supplier charges $44 per candle for the rush order, what is Evergreen's cost of understocking (Cu) when placing the regular order (i.e., the order at standard cost)?