Table:
0
A
B
C
D
E
F
1
Team
Outgoing manager
Manner of departure
Date of vacancy
Incoming manager
Date of appointment
2
Warri Wolves
Lawrence Akpokona
fired
end of 2009-10 season
Paul Aigbogun
2 September 2010
3
Kwara United
Justin Tenger
fired
end of 2009-10 season
Kadiri Ikhana
17 July 2010
4
Sunshine Stars
Solomon Ogbeide
fired
Aug. 18 2010
Gbenga Ogunbote
Aug. 18 2010
5
Gombe United
Ben Duamlong
Resigned
Oct.8 2010
Bernard Ogbe
Nov. 5 2010
6
Heartland
Samson Siasia
resigned to take Super Eagles job
Dec. 1 2010
Lodewijk de Kruif
Feb. 7 2011
7
Niger Tornadoes
Ladan Bosso
fired
Nov. 26 2010
Samson Unuanel (interim)
Nov. 26 2010
8
Crown F.C.
Ganiyu Salami
fired
Jan. 22 2011
Oladunni Oyekale
Jan. 22 2011
9
Kano Pillars F.C.
Salisu Yusuf
resigned to become Super Eagles assistant
Jan. 1 2011
Ladan Bosso
Jan. 23 2011
10
Niger Tornadoes
Samson Unuanel
interim period ends
Feb. 6 2011
Justin Tenger
Feb. 6 2011
11
JUTH F.C.
Tunde Abdulrahman
fired
Feb. 17 2011
Emmanuel Gustave Deutsch
Feb. 28 2011
12
Ocean Boys F.C.
Larry Eceli
fired
May 20, 2011
Samson Unuanel
May 20, 2011

Questions and formulas:
Question: when was the next coach appointed after niger tornadoes fired their coach?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:F1,(C1="fired")*(A1="Niger Tornadoes")),6))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:F12,(C2:C12="fired")*(A2:A12="Niger Tornadoes")),6))
Level: medium
Question: how many managers left sunshine stars?
Formula: ROWS(UNIQUE(FILTER(B1, A1="Sunshine Stars")))
Formula2: ROWS(UNIQUE(FILTER(B2:B12, A2:A12="Sunshine Stars")))
Level: medium
Question: how many new managers replaced  manager(s) who resigned? 
Formula: ROWS(UNIQUE(FILTER(E1, C1="Resigned")))
Formula2: ROWS(UNIQUE(FILTER(E2:E12, C2:C12="Resigned")))
Level: medium
Question: how many times did tunde abdulrahman leave the team?
Formula: ROWS(UNIQUE(FILTER(D1, B1="Tunde Abdulrahman")))
Formula2: ROWS(UNIQUE(FILTER(D2:D12, B2:B12="Tunde Abdulrahman")))
Level: medium