 In total U @-@ 70 sank 54 ships with a combined tonnage of 139 @,@ 065 and damaged four with a tonnage of 20 @,@ 369 in her twelve war patrols . She was surrendered to the British on 20 November 1918 , nine days after the Armistice , and broken up at Bo 'ness in 1919 – 20 . 
