Answer: 0.8g/cm^3
Step-by-step explanation:
In seeing your problem, I see an issue with your units for centimeter. The volume is in the third dimension, so we use cm^3 every single time for the volume. That way, we can arrive to the correct density (in g/cm^3)
Density = mass/volume and so
Density = 8g/10cm^3
= 0.8g/cm^3