Final answer:
Lynda should choose research questions that build on her existing knowledge of diet and health, impacting her project with thorough investigation and relevant insights.
Step-by-step explanation:
When Lynda is deciding on the next step for her research project on diet and health, she should ask questions that will elaborate on the initial understanding from her notes. A good research question could explore the impact of diet on certain illnesses, like depression, which would build on her note that diet affects health. Alternatively, investigating global food-related health issues could provide a broader context to her report. She could also compare American dietary patterns to European ones to understand cultural dietary differences. Lastly, looking into government dietary guidelines will provide a baseline of what is recommended for healthy eating.