钢轨侧面磨耗在钢轨里踏面(按标准断面)下16mm处测量。
参考答案:对
小红做一道数学题“两个多项式A、B,B为4x2-5x-6,试求A+2B的值”.小红误将A+2B看成A-2B,结果答案(计算正确)为-7x2+10x+12.
(1)试求A+2B的正确结果;
(2)求出当x=3时A+2B的值.
It was raining outside, ,I couldn’t find a taxi.
A.to make things better
B.to make things worse
C.still worse
D.still better