refers to the ecological process involved in the concentric zone model in which a new category of people or type of land use arrives in an area previously occupied by another group or land use.

Invasion

Explanation:

Invasion refers to the ecological process involved in the concentric zone model in which a new category of people or type of land use arrives in an area previously occupied by another group or land use

Concentric zone model is a one of the first theoretical  model created by Ernest Burgess in 1925 in a bid to explain urban social structures . the model views  cities as a series of five circular rings or zones that starts from a central district or area usually a business district

this is an outline for the decisions that frankie is going to make

opportunity cost

willingness to buy

price or quality

of course, there could be many economic strategies that should be considered important while making decision. opportunity cost is the foremost significant factor while considering any economic option. when you buy something, you should know how much you are forgoing for this product. indeed, you could buy something different with this measure if you changed your mind. willingness to buy shows how much surplus you are earning while making a decision. it is important because it shows you buy what you want or you buy because you have only limited amount of money. the price or quality can be considered as a general economic option that we are applying while buying something. when you buy something, price or quality could be one of the options. indeed, they define the characteristics of the product.    

mark brainliest!

i would say b. research typically uses a variety of sources