Final answer:
The mass of the rock is calculated by multiplying its density (2.7 g/mL) with its volume (13 mL), resulting in a mass of 35.1 grams.
Step-by-step explanation:
Density is defined as mass per unit volume. We can find the mass of the rock by multiplying its density and volume. In this case, the density of the rock is 2.7 g/mL and the volume is 13 mL.
Using the formula, mass = density x volume, we can calculate the mass as:
mass = 2.7 g/mL x 13 mL = 35.1 g