Answer:
Volume = 10ml
Density = 1/5 g/ml or 0.20g/ml
Step-by-step explanation:
The rocks are 10ml since the initial volume went up by 10.
Since density = mass/volume, you divide 2 by 10.
D = 2/10
D = 1/5 g/ml or 0.20g/ml
(Unit is g/ml aka grams/millileter)