CREATE TABLE table_67856 ("Year" FLOAT, "Team" TEXT, "Co-Drivers" TEXT, "Class" TEXT, "Laps" FLOAT, "Pos." TEXT, "Class Pos." TEXT)

How many laps did the 6th placed in 1998 complete?
SELECT SUM("Laps") FROM table_67856 WHERE "Pos." = '6th' AND "Year" = '1998'
SELECT SUM("Laps") FROM "table_67856" WHERE "Pos." = '6th' AND "Year" = '1998'