Choose n if the state is in the northeast region. choose s if the state is in the south region. choose m if the state is in the midwest region. choose w if the state is in the west region.
alabama
vermont
maine
illinois
arizona
indiana
california
louisiana

Alabama  --- S

Vermont  --- N

Maine  --- N

Illinois  --- M

Arizona  --- W

Indiana  --- M

California  --- W

Louisiana --- S

Explanation:

-The Northeastern United States form a region in United States bordered on the north by Canada, on the east by the Atlantic Ocean, on the south by the Southern United States and in the west by the Midwest. The region covers the northern half of the East Coast. Northeast states include Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey and Pennsylvania.

-The Southern United States is group of sixteen states in the southeast. The states included in this region are Alabama, Arkansas, Delaware, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, Oklahoma, North Carolina, South Carolina, Tennessee, Texas, Virginia, and West Virginia. [1] The Columbia District is also considered as part of the South. Approximately 130,000,000 people live in the Southern United States.

-The Midwest is a census region of the United States of America located just east of the central area of the country. It is in turn composed of two census divisions: East North Central and West North Central. At the federative level, the region is made up of eight states that collect 20% of US population, which are:  Illinois , Indiana , Iowa , Michigan , Minnesota , Missouri , Ohio , and Wisconsin .

-The American West traditionally refers to the western states of the United States. As the United States expanded westward after its founding, the concept of "the west" has expanded over time: before the 1800s, the Appalachians were seen as the western frontier, then the frontier moved westward and the Mississippi River was considered the western frontier.  

The western United States is the largest area of the country, covering more than half of the United States. The states in the area can be divided into the Pacific states of Alaska, California, Hawaii, Oregon and Washington, and the mountain states of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming.