需要三相四线制配电的电缆线路可以采用四芯电缆外加一根绝缘导线代替。
参考答案：错
Which of the following statements regarding confidence intervals is TRUE（）
A. The higher the alpha level, the wider the confidence interval.
B. The relationship between the alpha level and the confidence interval cannot be ascertained.
C. The lower the alpha level, the wider the confidence interval.
往复泵的主要构件有哪些？
