What about the canadian labor force shows that the country is in the postindustrial stage

Natural border is something that separates countries or states.

Physical border is something that separates countries or states.

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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