Use the In$-$class exercise from Lecture $7($be sure to use the excel file from Unit $7)$ for this problem. Assume that the cost per unit can be decreased to $$12$ by using cheaper raw materials to produce the shelves. As news of the lower quality shelves spreads, we also expect that units sold will decrease by $7\%$ per year. All other assumptions remain the same. What is the new NPV$?$