EXERCISE $5$

Consider the relation $R1(A,B,C,D,E,F)$ with the following functional dependencies

$A,BC,(1)$

$CB,(2)$

$CD$

$B,CF(4)$

$DE,(5)$

Find all candidate keys of R$1.(2$ PTS$)$

Is $R1$ in $2NF?$ Justify your answer. $(1$ PT$)$

Is R$1$ in $3$NF$?$ Justify your answer. $(1$ PT$)$

Is R$1$ in BCNF$?$ Justify your answer. $(1$ PT$)$