Table: olympic_sailing_1968
Columns: rank
nation
gold
silver
bronze
total

Question: What is the lowest Total, when Silver is greater than 7, and when Gold is greater than 73?
SQL: SELECT MIN("total") FROM olympic_sailing_1968 WHERE "silver" > 7 AND "gold" > 73

Question: What is Total, when Silver is less than 65, when Bronze is greater than 4, and when Rank is "4"?
SQL: SELECT "total" FROM olympic_sailing_1968 WHERE "silver" < 65 AND "bronze" > 4 AND "rank" = '4'

Question: What is the average Silver, when Gold is less than 0?
SQL: SELECT AVG("silver") FROM olympic_sailing_1968 WHERE "gold" < 0