CREATE TABLE table_71688 ("Year" TEXT, "Start" TEXT, "Qual" TEXT, "Rank" TEXT, "Finish" TEXT, "Laps" FLOAT)

What was the lowest lap with the ranking of 19?
SELECT MIN("Laps") FROM table_71688 WHERE "Start" = '19'
SELECT MIN("Laps") FROM "table_71688" WHERE "Start" = '19'