Final answer:
The Rough Riders, San Juan Hill, and the Tenth Negro Cavalry were key military units in the Spanish-American War, with the Rough Riders led by Theodore Roosevelt playing a significant role in the capture of San Juan Hill.
Step-by-step explanation:
The Rough Riders, San Juan Hill, and the Tenth Negro Cavalry were key military units in the Spanish-American War. The Rough Riders, led by Theodore Roosevelt, were an all-volunteer cavalry unit that played a significant role in the capture of San Juan Hill. The Tenth Negro Cavalry, made up of African American soldiers, also contributed to the American victory in Cuba.