Suppose Luke is indifferent between these two consumption bundles {3 pens, 2 notebooks} and {5 pens, 1 notebook}. How many pens Luke is willing to give up for an additional notebook? O a. 0.5 pen O b. 1 pen O c. . 3 pens O d. 2 pens [QUESTION 9 CONTINUED] Suppose Luke is indifferent between these two consumption bundles {3 pens, 2 notebooks} and {5 pens, 1 notebook}. How many notebooks Luke is willing to give up for an additional pen? O a. 2 notebooks O b. 3 notebooks O c. 0.5 notebook O d. 1 notebook