What types of spatial interaction, in this case international trade, between different countries would you expect based on the idea of distance decay? Give some hypothetical examples, using specific goods or services and countries.

Many types

Explanation:

The distance decay is the negative effect on spatial interaction (international trade) that might occur when the distance is bigger between the provider and the receiver. This was clearly the case in regions where the infrastructure is underdeveloped. Nowadays it doesn´t have such a big effect any more. Take the avocado market: Mexican producers earn sufficient enough to export them to the U.S. because the product itself is more important than the distance. The other way around: Coca Cola can be found in any remote Mexican village and sometimes even replaces drinking water (!). Again the distance decay has little effect here but cultural habits, very often molded by multinationals, do have their effect.  

most cajuns resided in acadiana, where their descendants are still predominant

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