Table: t_1929_vfl_match_4
Columns: home_team
home_team_score
away_team
away_team_score
venue
crowd
date

Question: What was the average crowd size when Melbourne was the home team?
SQL: SELECT AVG("crowd") FROM t_1929_vfl_match_4 WHERE "home_team" = 'melbourne'

Question: What was North Melbourne's score when they were the home team?
SQL: SELECT "away_team_score" FROM t_1929_vfl_match_4 WHERE "away_team" = 'north melbourne'