A$.$ Create an E$-$R model with one entity. Specify the identifier and attributes.

B$.$ Create an alternative E$-$R model with two entities, one for Customer and a

second for Subscription. Specify identifiers, attributes, relationship name, type,

and cardinalities.

C$.$ Under what conditions do you prefer the model in A to that in B$?$ Under what

conditions do you prefer the model in $B$ to that in $A?$