Suppose wanda´s widgets has a fixed proportions production function. It currently delivers 1000 widgets per month to its only customer. Currently, wanda´s costs are $2000 per month per machine and $4000 per month per worker. Wanda uses 20 machines and 10 workers to produce 1000 widgets each month. If the cost of machines fall to $1600 per month and wanda continues to produce 1000 widgets, what happens to total costs? Show this in a graph, using one isoquant and a pair of isocost lines. (Hint: what are the horizontal intercepts of the old and new isocost lines?)