Northwest Coast Indians enjoyed a varied diet, most likely because of their hunting techniques.
nomadic lifestyles.
farming techniques.
surrounding environment.

i believe its their nomadic lifestyle or surrounding enviroment.

Explanation:

there are treatment options for depression (mdd) that may work for you. one way of treating depression may be to affect the levels of certain chemicals that brain cells use to communicate, called neurotransmitters. scientists believe that certain neurotransmitters may be out of balance in depression.

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