PET scanning often uses labeled with the isotope F-18.

Apparent density of ethylene glycol 3350 = 17g/15.6mL= 1.09g/mL

Specific gravity of mixture = 1.01

Explanation:

The specific gravity of an object or substance is the ratio of the density of that object or substance to that of a reference substance usually water.

Specific gravity = density of substance/density of water

The density of a substance is the ratio of the mass of that substance to is volume.

Density = Mass/volume

Density of water 1.00 g/mL,  

Apparent density of ethylene glycol 3350 = mass/volume

volume of ethylene glycol = volume of mixture - volume of water

volume of ethylene glycol = 195.6 - 180) = 15.6mL

Apparent density of ethylene glycol 3350 = 17g/15.6mL= 1.09g/mL

mass of water =  density of water * volume of water

mass of water = 1.00g/mL * 180mL = 180 g

Mass of solution = mass of substance + mass of water = (17 + 180)g = 197g

Density of mixture = mass of mixture / volume of mixture

Density of mixture = 197 g / 195.6 mL = 1.01 g/mL

specific gravity of mixture = density of mixture / density of water

specific gravity of mixture = 1.01g/mL / 1.00g/mL

specific gravity of mixture = 1.01