Table: world_league_match
Columns: date
score
set_1
set_2
set_3
set_4
set_5
total

Question: What is the set 2 the has 1 set of 21-25, and 4 sets of 25-20?
SQL: SELECT "set_2" FROM world_league_match WHERE "set_1" = '21-25' AND "set_4" = '25-20'