$1)\frac{V_{CO_2}}{V_{H_2O}}=\frac{n_{CO_2}}{n_{H_2O}}=\frac{4}{5}\Rightarrow X:C_4H_9OH$$2)\frac{m_{H_2O}}{m_{CO_2}}=\frac{18n_{H_2O}}{44n_{CO_2}}=\frac{27}{44}\Rightarrow \frac{n_{H_2O}}{n_{CO_2}}=\frac{3}{2}\Rightarrow C_2H_4(OH)_2$
$3)\begin{cases}n_H=2n_{H_2O}=0,6 mol \\n_C=n_{CO_2}=0,3 mol\\n_O=\frac{5,8-(0,6.1+0,3.12)}{16}=0,1 \end{cases}\Rightarrow C_3H_5OH$
$4)\frac{n_{CO_2}}{n_{H_2O}}=\frac{3}{4}\Rightarrow C_3H_8O_n\Rightarrow \begin{cases}C_3H_7OH \\C_3H_6(OH)_2\\C_3H_5(OH)_3 \end{cases}$