Volume of solution is 60.0 mL and mass is 30.000 g. Density of a solution is defined as mass per unit volume.
Thus, density can be calculated as follows:
d=\frac{m}{V} ….. (1)
Here, d is density, m is mass and V is volume.
Putting the value of mass and velocity in the equation (1),
d=\frac{30.000 g}{60.0 mL}=0.5 g/mL
Thus, the density of a saline solution is 0.5 g/mL.