Answer:
For a: The volume of graphite is

For b: The volume of bromine is

Step-by-step explanation:
To calculate volume of a substance, we use the equation:
......(1)
Density of graphite =

Mass of graphite = 11.3 g
Putting values in equation 1, we get:

Hence, the volume of graphite is

Density of bromine =

Mass of bromine = 39.657 g
Putting values in equation 1, we get:

Hence, the volume of bromine is
