What are the differences and similarities between a fjord and an estuary? I will name brainliest if correct.

Both firth and fjord are now generally defined as an arm of the sea. The difference is crucial - a firth (or fjord) is made up of undiluted sea water, but an estuary has a gradation of salt water dilution from fully salt water at its mouth to fresh water at its head, and experiences tidal f luctuations.

Explanation:

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