Suppose that inventories were $40 billion in year 1 and $50 billion in year 2. For year 2, national income accountants would a. subtract $45 billion (= $90/2) from other elements of investment in calculating total investment. b. add $45 billion (=$90/2) to other elements of investment in calculating total investment. c. add $10 billion to other elements of investment in calculating total investment. d. subtract $10 billion from other elements of investment in calculating total investment.