Which of the following is true of net working capital?
a. when current assets of a firm exceed its current liabilities, a firm is said to have positive net working capital
b. when current assets of a firm exceed its total asset, the firm is said to have negative net working capital
c. when current assets of a firm are less than its total assets, a firm is said to have positive net working net working capital
d. when current assets of a firm exceed its current liabilities, a firm is said to have negative net working net working capital