Answer
The density of the liquid is $0.83~g/cm^3$
Work Step by Step
We can see that the points $0.20~m$ above the bottom on both sides of the tube have the same pressure. Then the gauge pressure due to the fluid above this point must be equal on both sides of the tube.
We can find the density $\rho_l$ of the liquid:
$\rho_l~g~h_l = \rho_w~g~h_w$
$\rho_l = \frac{\rho_w~h_w}{h_l}$
$\rho_l = \frac{(1.0~g/cm^3)(0.25~m)}{0.30~m}$
$\rho_l = 0.83~g/cm^3$
The density of the liquid is $0.83~g/cm^3$.
