Table:
0
A
B
C
D
1
county id
county name
population
zip code
2
1
Howard
21000
D21
3
2
Baltimore County
90000
D08
4
3
Colony
79000
D02
5
4
Mansfield
87200
D09
6
5
Manning
13300
D11

Questions and formulas:
Question: How many counties are there in total?
Formula: SUM(A1)
Formula2: SUM(A2:A6)
Level: easy
Question: Count the total number of counties.
Formula: SUM(A1)
Formula2: SUM(A2:A6)
Level: easy
Question: Show the county name and population of all counties.
Formula: CHOOSE({1,2},B1,C1)
Formula2: CHOOSE({1,2},B2:B6,C2:C6)
Level: easy
Question: What are the name and population of each county?
Formula: CHOOSE({1,2},B1,C1)
Formula2: CHOOSE({1,2},B2:B6,C2:C6)
Level: easy
Question: Show the average population of all counties.
Formula: AVERAGE(C1)
Formula2: AVERAGE(C2:C6)
Level: easy
Question: On average how large is the population of the counties?
Formula: AVERAGE(C1)
Formula2: AVERAGE(C2:C6)
Level: easy
Question: Show the zip code of the county with name "Howard".
Formula: FILTER(D1,B1="Howard")
Formula2: FILTER(D2:D6,B2:B6="Howard")
Level: easy
Question: What is the zip code the county named "Howard" is located in?
Formula: FILTER(D1,B1="Howard")
Formula2: FILTER(D2:D6,B2:B6="Howard")
Level: easy
Question: Return the names of all counties sorted by population in ascending order.
Formula: SORTBY(B1,C1,1)
Formula2: SORTBY(B2:B6,C2:C6,1)
Level: easy
Question: Sort the names of all counties in ascending order of population.
Formula: SORTBY(B1,C1,1)
Formula2: SORTBY(B2:B6,C2:C6,1)
Level: easy
Question: Return the name of county and sorted by county name in descending alphabetical order.
Formula: SORT(UNIQUE(B1), 1, -1)
Formula2: SORT(UNIQUE(B2:B6), 1, -1)
Level: easy
Question: Sort the names of all counties in descending alphabetical order.
Formula: SORTBY(B1,B1,-1)
Formula2: SORTBY(B2:B6,B2:B6,-1)
Level: easy
Question: Show the name of the county with the biggest population.
Formula: LET(a,SORTBY(B1,C1,-1),FILTER(a,SEQUENCE(ROWS(a))<=1))
Formula2: LET(a,SORTBY(B2:B6,C2:C6,-1),FILTER(a,SEQUENCE(ROWS(a))<=1))
Level: hard
Question: Which county has the largest population?.
Formula: TAKE(SORT(SUMMARIZE(A1,SUMX(C1)), 2, -1), 1)
Formula2: TAKE(SORT(SUMMARIZE(A2:A6,SUMX(C2:C6)), 2, -1), 1)
Level: hard
Question: Show the 3 counties with the smallest population.
Formula: LET(a,SORTBY(B1,C1,1),FILTER(a,SEQUENCE(ROWS(a))<=3))
Formula2: LET(a,SORTBY(B2:B6,C2:C6,1),FILTER(a,SEQUENCE(ROWS(a))<=3))
Level: hard
Question: What's Howard's zip code and id?
Formula: LET(query1,FILTER(A1:D1,B1="howard"),UNIQUE(CHOOSECOLS(query1,4,1)))
Formula2: LET(query1,FILTER(A2:D6,B2:B6="howard"),UNIQUE(CHOOSECOLS(query1,4,1)))
Level: hard
Question: the zip code of howard.
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:D1,B1="howard"),4))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:D6,B2:B6="howard"),4))
Level: medium
Question: Total number of counties 
Formula: SUM(A1)
Formula2: SUM(A2:A6)
Level: easy
Question: The number of countries.
Formula: SUM(A1)
Formula2: SUM(A2:A6)
Level: easy
Question: country names from z to a.
Formula: SORT(UNIQUE(B1), 1, -1)
Formula2: SORT(UNIQUE(B2:B6), 1, -1)
Level: easy
Question: Country ids in descending order and their corresponding country names.
Formula: SORT(UNIQUE(HSTACK(B1,A1)), 2, -1)
Formula2: SORT(UNIQUE(HSTACK(B2:B6,A2:A6)), 2, -1)
Level: medium
Question: What's the name and id of the county with the biggest population?
Formula: LET(a,HSTACK(B1,A1),b,A1,c,CHOOSECOLS(TAKE(SORT(SUMMARIZE(A1,SUMX(C1)), 2, -1), 1),1),UNIQUE(FILTER(a,NOT(ISNA(XLOOKUP(b,c,c))))))
Formula2: LET(a,HSTACK(B2:B6,A2:A6),b,A2:A6,c,CHOOSECOLS(TAKE(SORT(SUMMARIZE(A2:A6,SUMX(C2:C6)), 2, -1), 1),1),UNIQUE(FILTER(a,NOT(ISNA(XLOOKUP(b,c,c))))))
Level: hard
Question: The id of the most populated county.
Formula: TAKE(SORT(SUMMARIZE(A1,SUMX(C1)), 2, -1), 1)
Formula2: TAKE(SORT(SUMMARIZE(A2:A6,SUMX(C2:C6)), 2, -1), 1)
Level: hard
Question: What are the ids of the 3 least populous countries?
Formula: TAKE(SORT(SUMMARIZE(A1,SUMX(C1)), 2, 1), 3)
Formula2: TAKE(SORT(SUMMARIZE(A2:A6,SUMX(C2:C6)), 2, 1), 3)
Level: hard
Question: Count of the counties.
Formula: SUM(A1)
Formula2: SUM(A2:A6)
Level: easy
Question: What's the zip code and id of howard?
Formula: LET(query1,FILTER(A1:D1,B1="howard"),UNIQUE(CHOOSECOLS(query1,4,1)))
Formula2: LET(query1,FILTER(A2:D6,B2:B6="howard"),UNIQUE(CHOOSECOLS(query1,4,1)))
Level: hard
Question: the country names from z to a.
Formula: SORT(UNIQUE(B1), 1, -1)
Formula2: SORT(UNIQUE(B2:B6), 1, -1)
Level: easy
Question: Country ids in descending order and the corresponding country names.
Formula: SORT(UNIQUE(HSTACK(B1,A1)), 2, -1)
Formula2: SORT(UNIQUE(HSTACK(B2:B6,A2:A6)), 2, -1)
Level: medium
Question: the name and id of the most populous county
Formula: TAKE(SORT(SUMMARIZE(HSTACK(B1,A1),SUMX(C1)), 3, -1), 1)
Formula2: TAKE(SORT(SUMMARIZE(HSTACK(B2:B6,A2:A6),SUMX(C2:C6)), 3, -1), 1)
Level: hard
Question: The id of the most crowded county.
Formula: TAKE(SORT(SUMMARIZE(A1,SUMX(C1)), 2, -1), 1)
Formula2: TAKE(SORT(SUMMARIZE(A2:A6,SUMX(C2:C6)), 2, -1), 1)
Level: hard
Question: The number of countries.
Formula: SUM(A1)
Formula2: SUM(A2:A6)
Level: easy