There is a small typo in the introductory text of the Unit 7: Designing Multi-Agent Systems.
The error is located in the text description just below the video by Brian.
Current sentence: "He specifically took a multi-agents system of vacuum cleaners and asked: how can can cooperate with each other?"
Suggested fix: "He specifically took a multi-agent system of vacuum cleaners and asked: how they/agents can cooperate with each other?"