I'll lower the price for a while. A reference book compiling problems from the 20 years between 2005 and 2024, organized by theme. - Title: 20 Years of Machines: Thoroughly Learning by Theme - Publication Year: 2025 Edition - Contents: 20 years worth of content from 2005 to 2024 - Genre: Qualifications/Certifications Thank you for looking. There are no markings. The cover was removed during use, so it shows some wear, but the inside has a well-used feel. Personal thoughts/opinions: I passed by studying only this book. Recent past exam questions are available online, so this book is, in a sense, valuable.