$A,B,C,E,F$ are atomic attributes.

$(1)AB$;

$(2)BC$;

$(3)A,BE$;

$(4)A,EF$;

$(5)A,FE$

$\}$

Explain when a fd finF is redundant?

Explain how to remove a fd in general.

Proof that fd $(5)$ A$,$ F $$ E ist redundant.

Apply the approach$-$by$-$synthesis to design a $3NF$ relational schema.