Table: league_one_managers_4
Columns: team
outgoing_manager
manner_of_departure
date_of_vacancy
replaced_by
date_of_appointment
position_in_table

Question: who is the replacement when the team is milton keynes dons?
SQL: SELECT "replaced_by" FROM league_one_managers_4 WHERE "team" = 'milton keynes dons'

Question: what is the team with the position in table of 24th and the date of appointment 15 september 2008?
SQL: SELECT "team" FROM league_one_managers_4 WHERE "position_in_table" = '24th' AND "date_of_appointment" = '15 september 2008'

Question: what is the position in table when the team is hartlepool united?
SQL: SELECT "position_in_table" FROM league_one_managers_4 WHERE "team" = 'hartlepool united'

Question: what is the team geraint williams is the replacement?
SQL: SELECT "team" FROM league_one_managers_4 WHERE "replaced_by" = 'geraint williams'

Question: what is the date of vacancy when the position in table is 16th and the outgoing manager is russell slade?
SQL: SELECT "date_of_vacancy" FROM league_one_managers_4 WHERE "position_in_table" = '16th' AND "outgoing_manager" = 'russell slade'