You are working as a marketing coordinator for a smart phone manufacturer. You have just realised that your manager is not familiar with the product life cycle stages. To address this issue, you need to prepare the following document for your manager. 1. Define and explain different stages of product life cycle.  2. Your company wants to use sustainability as a part of its value proposition. At which stage of the product life cycle do you suggest sustainability to be incorporated?  3. Why do you suggest that specific stage?