What does the Miller model imply about the effect of corporate debt on the value of the firm, that is, how do personal taxes affect the situation?

MINI CASE 

David Lyons, CEO of Lyons Solar Technologies, is concerned about his firm’s level of debt financing. The company uses short-term debt to finance its temporary working capital needs, but it does not use any permanent (long-term) debt. Other solar technology companies average about 30 percent debt, and Mr. Lyons wonders why they use so much more debt, and what its effects are on stock prices. To gain some insights into the matter, he poses the following questions to you, his recently hired assistant: