Final answer:
Katy Ramirez is using regression analysis to forecast sales by finding a direct association between past sales and per capita income.
Step-by-step explanation:
Katy Ramirez is using e) Regression analysis as a sales forecasting technique. This method involves examining historical data to identify trends and relationships between variables, such as per capita income closely associated with past sales in this context. Regression analysis provides a statistical model that can be used to predict future sales based on these relationships.