Tell me the work types of Anna Powierza.
select t1.work_type from journal_committee as t1 join editor as t2 on t1.editor_id = t2.editor_id where t2.name = "Anna Powierza"
What is her age?
select age from editor where name = "Anna Powierza"
Tell me the most common age of editors.
select age from editor group by age order by count(*) desc limit 1