Table:
0
A
B
C
D
E
1
Locomotive
Pre-conversion
Entered service (T)
Re-entered service (P)
Owner
2
P11
T336
9 May 1956
5 June 1984
V/Line Passenger
3
P12
T329
18 June 1956
7 June 1984
V/Line Passenger
4
P13
T340
30 October 1956
10 July 1984
V/Line Passenger
5
P14
T330
2 July 1956
1 August 1984
V/Line Passenger
6
P15
T344
9 December 1956
22 October 1984
V/Line Passenger
7
P16
T332
22 July 1956
23 November 1984
V/Line Passenger
8
P17
T327
28 May 1956
19 December 1984
V/Line Passenger
9
P18
T339
7 October 1956
15 February 1985
V/Line Passenger
10
P19
T331
2 July 1956
26 March 1985
Pacific National - Rural and Bulk
11
P20
T337
23 September 1956
29 May 1985
Pacific National - Rural and Bulk
12
P21
T338
23 September 1956
27 June 1985
Pacific National - Rural and Bulk
13
P22
T328
18 June 1956
11 September 1985
Pacific National - Rural and Bulk
14
P23
T326
28 May 1956
11 September 1985
Pacific National - Rural and Bulk

Questions and formulas:
Question: Who owns the item that was a T326 before conversion and re-entered service on 11 September 1985?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,(D1="11 september 1985")*(B1="t326")),5))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E14,(D2:D14="11 september 1985")*(B2:B14="t326")),5))
Level: medium
Question: What date did the T328 that entered service on 18 June 1956 re-enter service?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,(C1="18 june 1956")*(B1="t328")),4))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E14,(C2:C14="18 june 1956")*(B2:B14="t328")),4))
Level: medium
Question: Which of V/Line Passenger's pre-conversions re-entered service on 23 November 1984?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,(E1="v/line passenger")*(D1="23 november 1984")),2))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E14,(E2:E14="v/line passenger")*(D2:D14="23 november 1984")),2))
Level: medium
Question: Who owns the locomotive that entered service on 30 October 1956?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,C1="30 october 1956"),5))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E14,C2:C14="30 october 1956"),5))
Level: medium