Caused a statement where neither the Allied nor the central powers could advance there's a machine gun, tank, trench warfare, u-boat, battleship chemical weapon, gas mask airplane

Which german count invented the zeppelin

What was zheng he’s most important accomplishment? zheng he spread chinese ideas and brought wealth to china from his travels. zheng he commanded an impressive fleet of ships. zheng he sailed the indian ocean and around africa. zheng he conquered lands as far away as africa to increase the dynasty’s power.

Public domain. which of these completes the diagram?