All 3 pictures were taken on or shortly after August 28, 1915 at Plymouth Harbour
Either H.M.S. Cambrian or H.M.S. Flora - Astrea-Class Protected Cruisers.
Believe this to be H.M.S. Sutlej -
Cressy-Class Armoured Cruiser
This is H.M.S. Vengeance - Canopus-Class Battleship