My coworker isn’t available during the day often and takes long lunches, is also doing a masters program. I’m not sure how to address this with him?

He's only your co-worker, so you have no control over him. Do his actions negatively affect your work? If not, say nothing to him or anyone else. If yes, then mention to him that you're concerned about his long lunches, that it negatively affect work, and see what his response is. If he does nothing to change things, then mention it to your boss, being sure to say that the co-worker's actions negatively affect your work.
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3Opinion
Don't, bring it up with his manager.
I did. She said she’s questioned his avail before too
She ended his contract starting next month.
Sideshow? Ok, I am so lost...
Tell your boss.
She’s brought it up before to me that I shouldn’t ask him for help and that she’s questioned his availability many times before too.
Lmfao no we work remote 😂 no they hate each other
Oh I thought you meant something sexual by side show
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