select avg(N.number) as Average
--just average from task 7
from (
	select t.team_name, count(tt.team_id) as 'Number'
	from teams as t
	join (
	    select t.team_id, t.team_name
	    from teams as t
	    join employees as e on e.team_id = t.team_id
	    where e.gender = 'F'
	) as tt on t.TEAM_ID = tt.team_id
	group by t.team_name
	UNION
	-- just solution from task 6:
	select distinct t.team_name, '0'
	from teams as t
	where t.team_name not in (
	    select distinct t.team_name
	    from teams as t
	    join employees as e on t.team_id = e.TEAM_ID
	    where e.gender = 'F'
	)
) as N