在质量改善中，经常要用到各种改善工具，请问QC新七种工具是哪几种？
参考答案：
亲和图、关联图、树状图、矩阵图、箭形图、过程决定计划图、矩阵资料解析法。
如果f[f（x）]=2x-1，则一次函数f（x）=______．
________ help the people in the snowstorm in the South made him worried.
A．Not known how to
B．Unknown what to do to
C．His knowing not how to
D．His not knowing how to
