The BeneCO database consists of $4$ tables EMPLOYEE, BENEFIT, JOB, PLAN that reflect the

following relationships:

$$ An EMPLOYEE has only one JOB$\_$CODE, but a JOB$\_$CODE can be held by many EMPLOYEEs.

$$ An EMPLOYEE can participate in many PLANs, and any PLAN can be assigned to many

EMPLOYEEs.

Note also that the M:N relationship has been broken down into two $1$:M relationships for

which the BENEFIT table serves as the composite or bridge entity.

Your tasks are:

$1.$ For each table in the database, identify the primary key and the foreign key$($s$).$ If a table

does not have a foreign key, write None.

$2.$ Create Entity$-$Relationship diagram