What does 503 service temporarily unavailable mean?

Dr. wisteria is a prominent chiropractor in the chicago area. she wants to provide a forum for her patients to discuss their health concerns and to seek and offer advice to other patients. which telecommunications tool is most appropriate for dr. wisteria's needs?

Write an algorithm to check if a number is even or odd and show with flow chart step by step

Does anyone have the problem where you try to watch a video to get your answer but it brings up a thing asking your gender to make ads relevant but it doesn't load? btw i won't be able to see the answer so use the comments .