Answer: The mass of lead is 16.872 g
Step-by-step explanation:
To calculate mass of a substance, we use the equation:
......(1)
Density of mercury =

Mass of mercury = 20.1 g
Putting values in equation 1, we get:

The volume of mercury is
which is equal to the lead sample.
We are given:
Density of lead =

Volume of lead =

Putting values in equation 1, we get:

Hence, the mass of lead is 16.872 g