Question $1$: $(5$ marks$)$

Draw the entity$-$relationship model of the flight database above. Describe your modeling choices in detail $($entities$,$ attributes, and cardinalities$).$

$1.$ The credit limit check parameter $($ChkCr$-$ID$)$ specifies the type of credit check $($e$.$g$.,$ no check, simple check$)$ applied to each sales document type $($SaTy$-$ID$).$ Each sales document type is linked to only one ChkCr$-$ID$.$