Answer:
Natural border is something that separates countries or states.
Physical border is something that separates countries or states.
Step-by-step explanation:
Natural border: Rivers, mountain ranges, oceans, and deserts can all serve as physical boundaries. Many times, political boundaries between countries or states form along physical boundaries.
Physical border: Physical boundaries include oceans, cliffs, or valleys.
Natural and Physical borders are basically the same thing they are both not man made and can be used for political reasons.
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