Answered (απεκριθη). First aorist passive (deponent) of αποκρινομα with λεγων (saying), a common (only here in the Apocalypse) Hebrew redundancy in the Gospels (Mark 9:5). An elder intervenes, though no question has been asked to interpret the vision (Swete).

These (ουτο). Prophetic predicate nominative put before τινες εισιν (who are they). Note article repeated with στολας pointing to verse Revelation 7:9, and accusative also retained after περιβεβλημενο as there. Both "who" and "whence" as in Joshua 9:8.