Prompt: Can you provide a comprehensive guide on how to create an effective lead generation email that maximizes engagement and conversion rates, including step-by-step instructions, analysis, and best practices? Please cover key elements to include in the email, such as subject lines, content, calls to action, and overall structure, as well as strategies for personalization and segmentation to improve relevance and engagement. Additionally, can you provide examples of successful lead generation emails from reputable companies across various industries, and explain what makes them effective? Finally, can you offer guidance on how to measure the success of a lead generation email campaign, track key metrics, and adjust strategies as needed to optimize results?