良导体的趋肤深度（或穿透深度）为（）。

A、

B、

C、

D、

A、绝缘子串的片数

B、绝缘子的材质

C、线路绝缘的空气间隙

D、线路避雷器的个数

A、Emphasizes relevance

B、Emphasizes reliability

C、Provide detailed information about parts of the company, not just the company as a whole

D、Not including the monetary information

A、左侧，左侧

B、右侧，右侧

C、左侧，右侧

D、右侧，左侧

设函数由方程确定, 其中可微, 且则

A、

B、

C、

D、

.Until this time,the baby has had no problems in feeding. On examination, a small knot is palpated at the right costal margin. Which of the following disorders might be suspected?

A、Esophageal stenosis

B、Annular pancreas

C、Hypertrophic pyloric stenosis

D、Duodenal atresia

A、A.4

B、B.3

C、C.2

D、D.1