In January 2019 , United Airlines (UAL) had a market capitalization of $22.95 billion, debt of $13.56 billion, and cash of $4.04 billion. United Airlines had revenues of $41.39 billion. Southwest Airlines (LUV) had a market capitalization of $27.34 billion, debt of $3.27 billion, cash of $3.62 billion, and revenues of $22.23 billion. a. Compare the market capitalization-to-revenue ratio (also called the price-to-sales ratio) for United Airlines and Southwest Airlines. b. Compare the enterprise value-to-revenue ratio for United Airlines and Southwest Airlines. c. Which of these comparisons is more meaningful? Explain