Table:
0
A
B
C
D
E
F
1
Standard
Date
CO (g/kWh)
NO x (g/kWh)
HC (g/kWh)
PM (g/kWh)
2
Euro 0
1988–1992
12.3
15.8
2.6
none
3
Euro I
1992–1995
4.9
9.0
1.23
0.40
4
Euro II
1995–1999
4.0
7.0
1.1
0.15
5
Euro III
1999–2005
2.1
5.0
0.66
0.1
6
Euro IV
2005–2008
1.5
3.5
0.46
0.02

Questions and formulas:
Question: How many different standards have a PM of 0.02 g/kWh?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:F1,F1=0.02),1))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:F6,F2:F6=0.02),1))
Level: medium
Question: What's the HC for the Euro I standard?
Formula: SUMIFS(E1,A1,"Euro I")
Formula2: SUMIFS(E2:E6,A2:A6,"Euro I")
Level: easy
Question: What's the HC for the standard with NO x of 7.0 g/kWh?
Formula: SUM(FILTER(E1, D1=7))
Formula2: SUM(FILTER(E2:E6, D2:D6=7))
Level: easy
Question: What's the PM for the standard with 12.3 g/kWh CO?
Formula: LET(query1,SUMMARIZE(F1,SUMX(C1)),FILTER(query1,CHOOSECOLS(query1,2)=12.3))
Formula2: LET(query1,SUMMARIZE(F2:F6,SUMX(C2:C6)),FILTER(query1,CHOOSECOLS(query1,2)=12.3))
Level: hard
Question: What's the NO of the standard with HC of 1.23 g/kWh?
Formula: SUM(FILTER(D1, E1=1.23))
Formula2: SUM(FILTER(D2:D6, E2:E6=1.23))
Level: easy