Answer
a) $1.11\ g/cm^3$, ethylene glycol
b) Yes
Work Step by Step
a) Mass of the sample: $16.08-12.20=3.88\ g$
Volume of the sample $3.50\ mL=3.50\ cm^3$
Sample's density: $\rho=m/V=1.11\ g/cm^3$
The closest density is ethylene glycol's.
b) The density would be $1.1\ g/cm^3$, and although it would be technically possible to say it's ethylene glycol, acetic acid would be very close.
