Table:
0
A
B
C
D
E
1
State (class)
Vacator
Reason for change
Successor
Date of successors formal installation
2
Tennessee (2)
Estes Kefauver (D)
Died August 10, 1963
Herbert S. Walters (D)
August 20, 1963
3
California (1)
Clair Engle (D)
Died July 30, 1964
Pierre Salinger (D)
August 4, 1964
4
South Carolina (2)
Strom Thurmond (D)
Changed political parties
Strom Thurmond (R)
September 16, 1964
5
New Mexico (1)
Edwin L. Mechem (R)
Resigned November 3, 1964
Joseph Montoya (D)
November 4, 1964
6
Oklahoma (2)
J. Howard Edmondson (D)
Successor elected November 3, 1964
Fred R. Harris (D)
November 4, 1964
7
Tennessee (2)
Herbert S. Walters (D)
Successor elected November 3, 1964
Ross Bass (D)
November 4, 1964

Questions and formulas:
Question: Name the state class for resigned november 3, 1964
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,C1="Resigned November 3, 1964"),1))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E7,C2:C7="Resigned November 3, 1964"),1))
Level: medium