Asubstance which
melts/boils at a fixed temperature is a pure substance

Ithink the answer is a or d.

Answer    "a salt" would be the best answerexplanationsalts can be defined as ionic compounds that are neither acids nor bases. nacl is an example of a salt, and its ionic.an enzyme is an organic compound which is covalently bonded, not ionically bonded.acids are generally held together by covalent bondsan element does not need any bonds to exist

Declaration of independence basically declares war with britain while bill of rights is document with the rights of the people written down.

The best answer choice for it would be  aqueducthop eit and add me if you would like