Final answer:
Polk's gambits during the Mexican-American War included the Nueces River dispute, John Fremont's involvement, and the Bear Flag Revolt. These events ultimately contributed to the outbreak of the war.
Step-by-step explanation:
Polk's gambits during the Mexican-American War included the Nueces River dispute, John Fremont's involvement, and the Bear Flag Revolt. The border dispute between the United States and Mexico centered around the Rio Grande, which the US claimed as the border, while Mexico claimed the Nueces River. John Fremont, an American explorer, played a role in the conflict by leading expeditions into Mexican territory. The Bear Flag Revolt was a rebellion by American settlers in California against Mexican rule. These events ultimately contributed to the outbreak of the Mexican-American War.