Answer
$\rho = 1.5~g/cm^3$
Work Step by Step
The weight of the displaced water is equal to the weight of the body.
Then the mass of the displaced water is equal to the mass of the body.
Let $V$ be the volume of the body.
We can find the density of the water:
$\rho = \frac{m}{2V/3}$
$\rho = \frac{3}{2}\cdot \frac{m}{V}$
$\rho = \frac{3}{2}\cdot (0.98~g/cm^3)$
$\rho = 1.5~g/cm^3$
Note that the water is so dense because it is very salty.
