find the names of all wines produced by the St. Helena appelation.
select name from wine where appelation = "St. Helena"
which one is the most expensive?
select name from wine where appelation = "St. Helena" order by price desc limit 1
what is its price?
select max(price) from wine where appelation = "St. Helena"
also show the best score earned by these wines.
select max(price), max(score) from wine where appelation = "St. Helena"