1. The user requests a full downloadable PDF file containing 20 multiple-choice questions (MCQs) followed by 5 essay questions. 2. As an AI text-based assistant, I can generate the content for these questions but cannot create or provide downloadable files directly. 3. To fulfill the request, I can generate the questions in text form which the user can then copy into a document editor to create a PDF. 4. Since the request is not a math problem, I will provide a short, friendly message explaining this limitation.