How are watershed systems separated

The watersheds of creeks and rivers are separated from each other by land forms of higher elevation called ridge lines or mountain divides.

Explanation: drainage divide. Definition English: Water divide a k a Drainage divide, Because water runs downhill, topography defines the boundary of a watershed ridges or high points in a landscape form the line between one watershed and another.

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answer they showed that organic molecules such as amino acids could be produced from inoragnic molecules;