Complete combustion equations

What is the sum of the coefficients when this equation is balanced with the smallest whole numbers? $\ce{\_CH3CH(CH3)CH2CH2CH3 + \_O2 -> \_CO2 + \_H2O}$ A. 20 B. 37 C. 47 D. 53

What is the coefficient of oxygen when the equation for the complete combustion of butan-1-ol is balanced using the smallest whole numbers? The unbalanced equation is $\ce{C4H9OH + O2 -> CO2 + H2O}$. A. 4 B. 6 C. 7 D. 13

When the equation for the complete combustion of 1 mol of pentan-1-ol, $\ce{C5H11OH}$, is balanced, what is the sum of all the coefficients? Unbalanced equation: $\ce{C5H11OH(l) + O2(g) -> CO2(g) + H2O(l)}$ A. 19 B. 19.5 C. 20 D. 39

Complete combustion turns pentadecane entirely into carbon dioxide and water. Write the corresponding balanced equation.