Final answer:
The United States-Canada border along the 49th parallel is an example of a geometric boundary. This boundary was established through legal agreements and treaties during the presidency of Polk and is irrespective of physical and cultural features.
Step-by-step explanation:
The border between the United States and Canada along the 49th parallel is an example of a geometric boundary. A geometric boundary is a type of political boundary that is defined and delimited by straight lines or arcs, irrespective of physical and cultural features. These boundaries are generally determined through legal agreements and treaties such as the one depicted in your question, where President Polk proposed the 49th parallel as a division between US and British territories. Following initial British resistance, British eventually agreed to the designation, leading to the formal establishment of the 49th parallel as a border in June 1846. Thus, in reference to your question, the US-Canadian border that lies along the 49th parallel represents a clear example of a geometric boundary.
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