What are all the races held after 2014?
select * from races where year > 2014
What are the average fastest lap speed in those races in term of each race?
select avg(t2.fastestlapspeed), t1.name, t1.year from races as t1 join results as t2 on t1.raceid = t2.raceid where t1.year > 2014 group by t1.name
Show them in order of year.
select avg(t2.fastestlapspeed), t1.name, t1.year from races as t1 join results as t2 on t1.raceid = t2.raceid where t1.year > 2014 group by t1.name order by t1.year