题干
It's already 10 o'clock. I wonder how it________that she was two hours late on such a short trip.
A：came over
B：came out
C：came about
D：came up
答案(点此获取答案解析）
C
时，AgCl在水中的沉淀溶解平衡曲线如图所示。下列说法正确的是