Okay, the user wants me to translate "quarter-circle" into Polish. Let me think. The term "quarter-circle" refers to a quarter of a circle, which in geometry is called "ćwierćkola" in Polish. I should check if that's the correct term. Yes, "ćwierćkola" is the standard translation. Since the original content isn't in Polish, I need to provide the translation. No explanations, just the result. So the answer is "ćwierćkola".