What type of solution is gasoline?

When a solute is present in trace quantities,the following expression is used:

The density of $2 \ M \ MgBr_2$ solution is $1.2 \ g/mL$. Then the molality of the solution is ........ $m$.

Find out the mole fraction of glycerine in a solution containing $46 \ g$ of glycerine $(C_3H_8O_3)$ and $36 \ g$ of water $(H_2O)$.

What will be the molality of the solution containing $18.25 \ g$ of $HCl$ gas in $500 \ g$ of water (in $m$)?

$3.0\, g$ of oxalic acid $[(CO_2H)_2 \cdot 2H_2O]$ is dissolved in a solvent to prepare a $250\, mL$ solution. The density of the solution is $1.9\, g/mL$. The molality and normality of the solution,respectively,are closest to