What flatlands circle the northern and western coastline of the gulf of mexico?

The flatlands of the 'Gulf Coastal Plain' circle the 'northern and western coastline' of the Gulf of Mexico.

Explanation:

The Gulf Coastal Plain.

The Gulf Coastal Plain is a lowland in North America located in the southern United States and northeastern Mexico and bordering the Gulf Coast. In the northeast it passes into the Atlantic Lowland, in the north it borders on the Central Plains, the Appalachian and Ouachita Mountains.

It is crossed by the valleys of major rivers - the Mississippi, Alabama, Brazos and Rio Grande. There are many lakes along the coast, and its climate varies from subtropical in the north to tropical in the south.

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d. new methods of assembly are introduced.

explanation:

this allows for the goods to be made on a larger scale. not faster because now it is shown to be made better, hence the greater productivity in the question. it is calling for something new to be introduced.