Table:
0
A
B
C
D
E
1
State (class)
Vacator
Reason for change
Successor
Date of successors formal installation
2
New Jersey (1)
James Schureman (F)
Resigned February 16, 1800
Aaron Ogden (F)
Elected February 28, 1800
3
Delaware (1)
Henry Latimer (F)
Resigned February 28, 1800
Samuel White (F)
Appointed February 28, 1800
4
New York (1)
James Watson (F)
Resigned March 19, 1800
Gouverneur Morris (F)
Elected April 3, 1800
5
Massachusetts (2)
Samuel Dexter (F)
Resigned May 30, 1800
Dwight Foster (F)
Elected June 6, 1800
6
New York (3)
John Laurance (F)
Resigned sometime in August, 1800
John Armstrong (DR)
Elected November 6, 1800
7
Massachusetts (1)
Benjamin Goodhue (F)
Resigned November 8, 1800
Jonathan Mason (F)
Elected November 14, 1800

Questions and formulas:
Question: in which state where John Laurance (f) as a vacator?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,B1="John Laurance (F)"),1))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E7,B2:B7="John Laurance (F)"),1))
Level: medium
Question: when the vacator was Henry Latimer (f), what were the causes for modification?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,B1="Henry Latimer (F)"),3))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E7,B2:B7="Henry Latimer (F)"),3))
Level: medium
Question: how many times has Aaron Ogden (f), been a successor and has had a formal installation? 
Formula: ROWS(UNIQUE(FILTER(E1, D1="Aaron Ogden (F)")))
Formula2: ROWS(UNIQUE(FILTER(E2:E7, D2:D7="Aaron Ogden (F)")))
Level: medium