Answer
$$density =1.46 \mathrm{\ g} / \mathrm{mL}$$
Work Step by Step
we know that $$density \ of\ an\ object = \frac {mass\ of\ this\ object}{volume\ of\ this\ object}$$ in our practice example, the mass is the difference between the mass of the full and empty flask Then. $$density =\frac{291.4 \mathrm{\ g}-108.6 \mathrm{\ g}}{125 \mathrm{\ mL}}=1.46 \mathrm{\ g} / \mathrm{mL}$$
