How many poll sources are there?
select count ( poll_source ) from candidate
how many people are there?
select count ( people_id ) from people
Yes, how many are female, have gender "F"
select count ( * ) from people where sex = 'F'
Yes
select t2.unsure_rate from people as t1 join candidate as t2 on t1.people_id = t2.people_id where t1.sex = 'F'
yes
select t2.unsure_rate from people as t1 join candidate as t2 on t1.people_id = t2.people_id where t1.sex = 'M'