Generate a full detail guide on business analytics for beginners. The guide must demystify data. It should include detailed sections on: 1. How to set up Google Analytics and understand its dashboard. 2. A guide to the 5 most important metrics to track for any website (e.g., Users, Bounce Rate, Session Duration). 3. How to use data to answer specific business questions (e.g., 'Where is my best traffic coming from?'). 4. An introduction to A/B testing and how to measure results. Please include a supportive disclaimer.