Final answer:
There were significant advances in military technology between the Civil War and the beginning of World War I, including the introduction of machine guns, long-range artillery guns, aircraft, and submarines.
Step-by-step explanation:
In the time period between the Civil War and the beginning of World War I, there were significant advances in military technology. The spread of industrialization allowed for the production of more powerful weapons. Some of the key advancements during this time included the introduction of machine guns, long-range artillery guns, aircraft, and submarines. These advancements revolutionized warfare and had a major impact on the way battles were fought.