Table:
0
A
B
C
D
E
F
1
Season
Network
Episodes
Premiered
Ended
DVD set release date
2
1
NBC
30
18-Sep-1965
07-May-1966
05-Aug-2008
3
2
NBC
30
17-Sep-1966
22-Apr-1967
10-Mar-2009
4
3
NBC
26
16-Sep-1967
06-Apr-1968
09-Jun-2009
5
4
NBC
26
21-Sep-1968
29-Mar-1969
06-Oct-2009
6
5
CBS
26
26-Sep-1969
15-May-1970
08-Dec-2009

Questions and formulas:
Question: When dis cbs release the DVD set?
Formula: FILTER(F1,B1="cbs")
Formula2: FILTER(F2:F6,B2:B6="cbs")
Level: easy
Question: What is the total season number for episodes later than episode 30?
Formula: SUM(FILTER(A1,C1>30))
Formula2: SUM(FILTER(A2:A6,C2:C6>30))
Level: easy