Questions: For raw data to become useful to marketers, they must be stored in a data warehouse, transformed into information and knowledge, gathered from internal company sources, gathered from external sources, communicated to executives through a formal report.

The answer is: transformed into information and knowledge.

Explanation for each option:

1. Stored in a data warehouse: While storing data in a data warehouse is important for organization and accessibility, it does not inherently make the data useful. The data must be processed and analyzed to extract meaningful insights.

2. Transformed into information and knowledge: This is the correct answer. Raw data becomes useful when it is processed and analyzed to provide information and insights that can inform decision-making. This transformation involves organizing, interpreting, and contextualizing the data to create knowledge that marketers can use.

3. Gathered from internal company sources: Gathering data from internal sources is a step in the data collection process, but it does not make the data useful on its own. The data still needs to be analyzed and interpreted.

4. Gathered from external sources: Similar to internal sources, gathering data from external sources is part of data collection. However, the data must be processed and analyzed to become useful.

5. Communicated to executives through a formal report: Communicating data through a report is a way to share insights, but the data must first be transformed into information and knowledge before it can be effectively communicated and used for decision-making.