What are the three most critical components that a marketer needs to examine to segment a market effectively?

1. Identifiability (and measurability)
2. Accessibility
3. Responsiveness

1. Identifiability
    - the target market must be identifiable to determine which of the
      consumers belong to the segment. The target market must be well-
      defined and measurable, particularly in terms of population, income, and
      age bracket. 

2. Accessibility
    - this refers to the ease of reaching the identified market segment in terms
      of geography and economy with appropriate market strategies. 

3. Responsiveness
    - the target market should be evaluated if they will respond (i.e. purchase)
      the products and services created for them. There is little point in
      identifying a market, creating a product, and developing marketing
      strategies if the consumers themselves see little value in what is being
      offered to them. Thus, the products and services must meed the
      consumers' or organizations' needs. 

Answerreal gdp per person;