Database: european_football_2
Question: How much is the average build up play speed of the Heart of Midlothian team?
SQL: SELECT CAST(SUM(t2.buildUpPlaySpeed) AS REAL) / COUNT(t2.id) FROM Team AS t1 INNER JOIN Team_Attributes AS t2 ON t1.team_api_id = t2.team_api_id WHERE t1.team_long_name = 'Heart of Midlothian'