Table:
0
A
B
C
D
E
1
System
Year Introduced
S-100 slots
Internal Floppy Disk
Internal Hard Disk
2
Z-1
1976
21
n/a
n/a
3
Z-2
1977
21
n/a
n/a
4
System Zero
1980
4
n/a
n/a
5
System One CS-1
1981
8
2 x 5-inch
n/a
6
System One CS-1H
1981
8
1 x 5-inch
5 megabytes
7
System Two Z-2D
1978
21
2 x 5-inch
n/a
8
System Two Z-2H
1980
12
2 x 5-inch
11 megabytes
9
System Three
1978
21
4 x 8-inch
n/a

Questions and formulas:
Question: What is the value for internal floppy disk with s-100 slots greater than 8 introduced earlier than 1978?
Formula: LET(query1,LET(query1,FILTER(A1:E1,B1<1978),SUMMARIZE(CHOOSECOLS(query1,4),SUMX(CHOOSECOLS(query1,3)))),FILTER(query1,CHOOSECOLS(query1,2)>8))
Formula2: LET(query1,LET(query1,FILTER(A2:E9,B2:B9<1978),SUMMARIZE(CHOOSECOLS(query1,4),SUMX(CHOOSECOLS(query1,3)))),FILTER(query1,CHOOSECOLS(query1,2)>8))
Level: hard
Question: Which system introduced earlier than 1981 has an internal hard disk of 11 megabytes and less than 21 s-100 slots?
Formula: LET(query1,LET(query1,FILTER(A1:E1,(B1<1981)*(E1="11 megabytes")),SUMMARIZE(CHOOSECOLS(query1,1),SUMX(CHOOSECOLS(query1,3)))),FILTER(query1,CHOOSECOLS(query1,2)<21))
Formula2: LET(query1,LET(query1,FILTER(A2:E9,(B2:B9<1981)*(E2:E9="11 megabytes")),SUMMARIZE(CHOOSECOLS(query1,1),SUMX(CHOOSECOLS(query1,3)))),FILTER(query1,CHOOSECOLS(query1,2)<21))
Level: hard