Table:
0
A
B
C
D
E
1
Date
City
Opponent
Results¹
Type of game
2
February 27
İzmir , Turkey
Turkey
1:1
Friendly
3
March 27
Belgrade
Northern Ireland
4:1
Euro '92 Qualifier
4
May 1
Belgrade
Denmark
1:2
Euro '92 Qualifier
5
May 16
Belgrade
Faroe Islands
7:0
Euro '92 Qualifier
6
August 8
Aosta , Italy
Czechoslovakia
3:4 (pen.)
Friendly
7
September 4
Stockholm , Sweden
Sweden
3:4
Friendly
8
October 16
Landskrona , Sweden
Faroe Islands
2:0
Euro '92 Qualifier
9
October 30
Varginha , Brazil
Brazil
1:3
Friendly
10
November 13
Vienna , Austria
Austria
2:0
Euro '92 Qualifier

Questions and formulas:
Question: When is Northern Ireland the opponent?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,C1="northern ireland"),1))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E10,C2:C10="northern ireland"),1))
Level: medium