CREATE TABLE table_15844 ("State/territory" TEXT, "Text/background colour" TEXT, "Format" TEXT, "Current slogan" TEXT, "Current series" TEXT, "Notes" TEXT)

Name the background colour for the Australian Capital Territory
SELECT "Text/background colour" FROM table_15844 WHERE "State/territory" = 'Australian Capital Territory'
SELECT "Text/background colour" FROM "table_15844" WHERE "State/territory" = 'Australian Capital Territory'