4. (20 points) Suppose you are hired as a new manager of a firm producing 20 units of output with 10 units of labor and 5 units of capital. Assume the price of labor is $90 and the price of capital is $120. Along the isoquant, the MRTSLK is as noted in Table 1. Table 1 \"T 7 8 9 10 ll L Given the above graph and table: a) In detail, explain the optimizing decisions for minimize cost assuming you can only hire whole numbers of workers (Hint: think about the MC and MB of changing L). b) How much total cost will you be able to save by Changing the input combination