Table: canoe_2008_men_c2_2
Columns: rank
athletes
country
time
notes

Question: What is the notes entry for the row with a Time of 1:42.309?
SQL: SELECT "notes" FROM canoe_2008_men_c2_2 WHERE "time" = '1:42.309'

Question: What is the rank for China?
SQL: SELECT SUM("rank") FROM canoe_2008_men_c2_2 WHERE "country" = 'china'

Question: What is the time for Cuba, with a notes entry of QS?
SQL: SELECT "time" FROM canoe_2008_men_c2_2 WHERE "notes" = 'qs' AND "country" = 'cuba'