Below is a preliminary entity relationship $($ER$)$ data model for a stationary sales database. Extend and modify the ER data model using Crow's foot notation; create

appropriate identifiers and attributes for each entity. Explain how you went from first normal form $(1$NF$)$ to second normal form $(2$NF$)$ and how you achieved third

normal form $(3$NF$).$ Lastly justify the decisions that you make regarding minimum and maximum cardinality.

PURCHASE ITEM is

ID$-$Dependent on PURCHASE