What is the purpose of deriving a cluster ID variable in cluster analysis?

Interactions can be created and added to a linear regression model.
Which statement is true about interactions?

Refer to the exhibit:

Prior to performing a decision tree analysis, you need to assess the default Values of Classification and Model Type Properties for Sale Amount. The variable represents product purchase amounts from an organization's e-commerce website.
How do you want the decision tree algorithm to treat this variable?

What does adding an interaction effect in linear regression modeling allow you to capture?

When reviewing outlier details in linear regression, what factors should be considered when deciding whether to exclude outliers?