The average price of a gallon of gas in 2013 dropped $0.12 (3 percent) from $3.61 in 2012 (to $3.49 in 2013). Conduct a horizontal analysis by calculating the year-over-year changes in each line item, expressed in dollars and in percentages for the income statement of Chevron Corporation for the year ended December 31, 2013 (amounts in billions). (Decreases should be indicated by a minus sign. Enter your answers in billions (i.e., 10,000,000,000 should be entered as 10). Round percentage values to 1 decimal place.) 2-a.Conduct a vertical analysis by expressing each line as a percentage of total revenues. (Round percentage values to 1 decimal place.) 2-b.Excluding income tax and other operating costs, did Chevron earn more profit per dollar of revenue in 2013 compared to 2012? Yes No