题目

— We did well in the test.— Exactly. Ninethe students have passed the test. A . hundred B . hundred of C . hundreds D . hundreds of 答案：B小明从图所示的二次函数y=ax2+bx+c的图象中，观察得出了下面五条信息：①c＜0；②abc＞0；③a-b+c＞0；④2a-3b=0；⑤c-4b＞0，你认为其中正确信息的个数有（ ）A．2个B．3个C．4个D．5个