Five or six football teams hold a round-robin tournament, with rankings determined by points. Each pair of teams plays one match, with the winner getting two points, a draw giving each team 1 point, and the loser getting 0 points. If two (or more) teams have the same points, the ranking is decided by a draw. Questions:
(1) How many matches were played in total? What is the total points of the six teams?
(2) What is the maximum possible total points for the top three teams? What is the minimum possible total points for the top three teams?
(3) What is the lowest possible score for the second place? What is the lowest score that guarantees a place in the top two?
(4) What is the lowest possible score for the first place? What is the lowest score that guarantees the first place?
Five, (1)15 games, 30 points; (2)24 points, 15 points; (3)4 points, 9 points; (4)5 points, 10 points.