Calculate the earnings before interest and taxes (EBIT) for Company III, which had a net income of $400,000, interest expenses of $50,000, and taxes of $100,000. Explain the earnings before interest and taxes (EBIT) as a measure of a company's operating performance, indicating its profitability before accounting for interest and taxes. Discuss the significance of EBIT in financial analysis, capital structure decisions, and assessing operational efficiency.