Density = mass/volume
Mass of the plastic material: 3.48 g
Volume of the plastic material: 10 mL
Density of the object: (3.48 g)/(10 mL) = 0.348 g/mL.
The answer might differ if you have to round your answer to a certain number of significant figures. I disregarded the sig figs for 10 mL (only one sig fig). If you must consider it, your density would be 0.3 g/mL. I would advise you to just go with what you’ve learned so far.
