Answer: new inventions
Step-by-step explanation:
First new weapons' like lmg smg and pistols Second tanks, air planes, and armored vehicles where made and was a game changer to the British because the could just plow threw barbed wire Third radios where needed in tanks to communicate Fourth the treaty of Versie made Germany lose its air force, pay war debt demilitarizes the Rhineland which impacted heavily when the great depression came along hope this helps hope you do good on your tests =)