题目

There used to ___ a truck ____ and I can’t get through.A. be, in the way               B. be, in a wayC. being, on the way         D. being, by the way 答案：A已知二次函数y=ax2+bx+c的图象如下图所示，化简|a+b+c|-|a-b+c|-|2a+b|=    ．