Consider a database $($politics$)$ with the following schema:

states $($statecode: char$(2),$ population$\_2010$: integer, population$\_2000$: integer, population$\_1950$: integer, population$\_1900$: integer, landarea: float, name: char$(20),$ admitted$\_$to$\_$union: date$)$ statecode is the primary key

counties $($name: char$(30),$ statecode: char$(2),$ population$\_1950$: integer, population$\_2010$: integer$)$ statecode references states$($statecode$)$

senators $($statecode: char$(2),$ name: char$(40),$ affiliation: char$(1),$ took$\_$office: integer, born: integer$)$ statecode references states$($statecode$)$

name is the primary key

committees $($id: char$(5),$ parent$\_$committee: char$(5),$ name: char$(200),$ chairman: char$(40),$ ranking$\_$member: char$(40))$

id is the primary key

parent$\_$committee references committees$($id$)$

chairman references senators$($name$)$

ranking$\_$member references senators$($name$)$