File talk:Two redshifts.JPG
Jump to navigation
Jump to search
Hello. Why the four black arrow are double arrow, please? I can't understand the drawing. Thanks. Domsau2 (talk) 10:13, 8 May 2018 (UTC)
Hello. Why the four black arrow are double arrow, please? I can't understand the drawing. Thanks. Domsau2 (talk) 10:13, 8 May 2018 (UTC)[reply]