CREATE TABLE table_36711 ("Editor" TEXT, "Site" TEXT, "Style ,  clone of" TEXT, "Cost  (  US$  ) " TEXT, "Open source" TEXT, "Activity" TEXT)

Which source has a Cost free, and an Activity of some, and an Editor of markitup?
SELECT "Open source" FROM table_36711 WHERE "Cost ( US$ )" = 'free' AND "Activity" = 'some' AND "Editor" = 'markitup'
SELECT "Open source" FROM "table_36711" WHERE "Activity" = 'some' AND "Cost ( US$ )" = 'free' AND "Editor" = 'markitup'