Please explain if these are true or false statements!

e. Managers make superior returns on their purchases of their company's stock. This observation contradicts the strong form market efficiency. f. The "IPO underpricing" phenomenon refers to the fact that IPO shares are generally undervalued by underwriters. g. Other things equal, interest tax shield is more valuable for a more profitable firm. h. A change in a firm's cash dividend policy can signal new information about the firm's future earnings better than the decision to buy back the firm's equity shares. i. Unlike forwards and futures, options allow a firm to hedge downside risk, but still participate in upside potential