Rather than just providing answers, the book teaches a repeatable to handle any system design question: Go to product viewer dialog for this item. System Design Interview - An Insider's Guide: Volume 2
: Pay close attention to the "Back-of-the-envelope estimation" sections. This is a critical skill for justifying your resource requirements. Study the Diagrams
Differences between block, file, and object storage. System Design Interview – An Insider's Guide: Volume 2
Why Alex Xu's System Design Interview Volume 2 is the Gold Standard for Tech Prep