Mass is the product of density and volume (m = D x V) while density is ratio of mass per volume (D = m / V). Summary: 1.Mass is how much matter is present in a particular object. 2.Density is how much mass is present per unit of volume.
asâ¢sert /ÉËsÉrt/USA pronunciation v. [~ + object] 1  to state strongly or positively; declare strongly:asserted his innocence.[~ + (that) clause]asserted that he was innocent of the crime. 2  to make a claim to:Minorities are now asserting their right to be heard.
1. to continue or retain; keep in existence. 2. to keep in proper or good condition: to maintain a building. 3. to support a style of living: the money maintained us for a month. 4. (takes a clause as object) to state or assert: he maintained that Talbot was wrong. 5. to defend against contradiction; uphold: she maintained her innocence.