A production interview usually adds a condition after your first answer: the batch repeats, an event arrives late or one key has most of the data. Recheck the design when that happens. A solution that produces the right rows once may still lose history or create duplicates after a restart.
These questions ask for explicit change and recovery rules. You will calculate a stream-quality summary, preserve the business meaning of event deduplication and explain what a local test can establish about distributed behavior. The browser executes the notebook tasks on its documented local subset. It cannot prove a cluster speedup or reproduce a live source's delivery guarantees. For each design choice, identify the durable state, the business key and the point where progress is committed. If those are unspecified, the recovery claim is incomplete.