$1.$ Analyze the spreadsheet shown in Figure $4-30$ and list all of the problems that occur when trying to track the assignment of sheet music using this spreadsheet. Also describe a report the choir master might like to see from this data.

$2.$ Figure $4-31($a$)$ shows a two$-$table data model for the sheet$-$music$-$tracking problem.

a$.$ Select primary keys for the ChoirMember and Work tables. Justify your selection.

b$.$ This design does not eliminate the potential for data integrity problems that occur in the spreadsheet. Explain why not.

c$.$ Design a database for this data model. Specify primary key and foreign key columns.