Table:
0
A
B
C
1
ssn
name
scientists
2
123234877
Michael Rogers
3
152934485
Anand Manikutty
4
222364883
Carol Smith
5
326587417
Joe Stevens
6
332154719
Mary-Anne Foster
7
332569843
George ODonnell
8
546523478
John Doe
9
631231482
David Smith
10
654873219
Zacary Efron
11
745685214
Eric Goldsmith
12
845657245
Elizabeth Doe
13
845657246
Kumar Swamy

Questions and formulas:
Question: Find the total number of scientists.
Formula: ROWS(UNIQUE(C1))
Formula2: ROWS(UNIQUE(C2:C13))
Level: easy
Question: How many scientists are there?
Formula: ROWS(UNIQUE(C1))
Formula2: ROWS(UNIQUE(C2:C13))
Level: easy
Question: What are the names of the scientists from 'a' to 'z'?
Formula: SORT(UNIQUE(HSTACK(B1,C1)), 1, 1)
Formula2: SORT(UNIQUE(HSTACK(B2:B13,C2:C13)), 1, 1)
Level: medium
Question: Scientists' names in alphabetical order
Formula: SORT(UNIQUE(HSTACK(C1,B1)), 2, 1)
Formula2: SORT(UNIQUE(HSTACK(C2:C13,B2:B13)), 2, 1)
Level: medium
Question: How many scientists are there?
Formula: ROWS(UNIQUE(C1))
Formula2: ROWS(UNIQUE(C2:C13))
Level: easy
Question: What is the total number of scientists?
Formula: ROWS(UNIQUE(C1))
Formula2: ROWS(UNIQUE(C2:C13))
Level: easy
Question: How many scientists?
Formula: ROWS(UNIQUE(C1))
Formula2: ROWS(UNIQUE(C2:C13))
Level: easy
Question: What is the number of scientists?
Formula: ROWS(UNIQUE(C1))
Formula2: ROWS(UNIQUE(C2:C13))
Level: easy
Question: The names of scientists from a to z.
Formula: SORT(UNIQUE(HSTACK(B1,C1)), 2, 1)
Formula2: SORT(UNIQUE(HSTACK(B2:B13,C2:C13)), 2, 1)
Level: medium