Table: miss_united_continent_results
Columns: rank
country
miss_united_continent
virreina
1st_ru
2nd_ru
3rd_ru
4th_ru
semifinalists
total

Question: How many 3rd ru does Costa Rica have? 
SQL: SELECT MAX("3rd_ru") FROM miss_united_continent_results WHERE "country" = 'Costa Rica'

Question: How many 3rd ru does Canada have? 
SQL: SELECT COUNT("3rd_ru") FROM miss_united_continent_results WHERE "country" = 'Canada'

Question: What is the least number of miss united continents? 
SQL: SELECT MIN("miss_united_continent") FROM miss_united_continent_results