Antibodies can destroy pathogens by (i) binding to and blocking the pathogen's receptors, thus causing neutralization of the pathogen, (ii) binding to the pathogen and activating complement, and (iii) binding to the pathogen and facilitating its opsonization and uptake by macrophages, which utilize their Fc receptors ...
Answer: The density of lead will be 
Explanation:
Density is defined as the mass contained per unit volume.

Given : Mass of lead=
Volume of lead =
Putting in the values we get:

Thus density of lead will be 