Your question is Meaning of HTTP 502. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
What does a response code of 502 mean?
Explain the HTTP meaning of the status code, identify the components involved, and distinguish it from related 4xx and 5xx responses. Briefly describe the first checks you would perform when diagnosing it.