WW1 Technology and Events

2. A promise between countries promising that they will protect each other if attacked
4. This battle was the deadliest of World War 1
8. Kind of ship used to carry airplanes
10. This was signed by France and Germany, officially ending the war; It is also now an international holiday
12. Tactic used across the western front which created a stagnant front line
14. This treaty punished Germany and created the League of Nations, as well as many other things
17. Long range cannons with high-explosive shells
18. This event in Russia gave Russia a new kind of government and pulled Russia out of the war
20. First and last name of the archduke that was assassinated, which led to Austria-Hungary declaring war on Serbia

1. A weapon used for clearing trenches by burning them
3. A telegram that was intercepted by Britain which talked about Germany allying with Mexico to attack America
5. Submarine used by Germany
6. This alliance was made up of Germany, Austria-Hungary, and the Ottoman Empire
7. Gun with a high fire-rate which created the need for trench warfare
9. Handheld explosive that could be thrown
11. An armored vehicle with cannons and machine guns that was used to approach trenches
13. Flying vehicle that was used for scouting and attacking
15. Famously used chemical weapon that is now illegal
16. A kind of communication that was used on the battlefield
17. This alliance was made up of Britain, France, Russia, and the United States
19. A cruise ship that was sunk by a German U-boat, which angered America