Since Master Windu has his arms at his sides, he feels relaxed at the topic,
so it's a Jedi afair. Master Kenobi has his arms folded at his chest, so he's trying to persuade them of something with superior intelligence. Jedi Knight Anakin Skywalker has his fists at his hips, so he is annoyed/aggrivated at something. Palpatine has his hands folded, like always, so I cant tell anything from him. I think their discussing the rank of Master. Oh Hi, I'm the guy who overexplains stuff btw