During the lecture of Rob Bauer on sustainability, what was a reason why it might be hard to change the cost of capital or governance in a company such as Walmart? O The Walton family hold a significant stake at the company and any divestment from other investors might not be potent. O Walmart is using an excess amount of convertible debt and thus, the cost of capital is hard to estimate. O The beta of Walmart is exceeding 2.5 and therefore the cost of capital is not that sensitive to divestments. O Walmart is using an excess amount of debt and thus, the cost of capital carries a significant tax shield