In 2020, Caterpillar Incorporated had about 540 million shares outstanding. Their book value was $44.4 per share, and the market price was $96.70 per share. The company's balance sheet shows that the company had $29.55 billion of long-term debt, which was currently selling near par value.

a. What was Caterpillar's book debt-to-value ratio?

Note: Do not round intermediate calculations. Enter your answer as a decimal rounded to 2 decimal places.

b. What was its market debt-to-value ratio?

c. Which measure should you use to calculate the company's cost of capital?