The relation $($second$)$ with S$ as key is:

S$ status city

S$120$ London

S$210$ Paris

S$310$ Paris

S$420$ London

S$530$ New York

There is a dependency of status from the city. $($functional dependency$)($f$.$e$.$ all the suppliers in London must have the status $20).$ The status and city are not functionally depended on the key S$$.$ Status and city are not mutually independent

a$.$ Examine if it is : $1$NF$,2$NF$,3$NF$,$ BCNF $($give explanation$).$

b$.$ If it is not a $3$NF how we can take a $3$NF $?$