什么是牵引变电所电气主结线图，并简述其工作过程。
题型：问答题 简答题
问题：
什么是牵引变电所电气主结线图，并简述其工作过程。
题型：问答题 简答题
根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
__小题1:__ Scientists and experts have proved the uniqueness of finger-prints and discovered that no exactly similar pattern is passed on from parents to children, though nobody knows why this is the cas
e.
The ridge(隆起) structure on a person’s fingers does not change with growth and is not affected by surface injuries. Burns, cuts and other damage to the outer part of the skin will be replaced in time by new one, which bears a reproduction of the original pattern. __小题2:_ Some criminals make use of this fact to remove their own finger-prints but this is a dangerous and rare step to take.
Finger-prints can be made very easily with printer’s ink. They can be recorded easily. __小题3:_ Because of the simplicity and economy of this system, finger-prints have often been used as a method of solving criminal case. A suspected man may deny a charge but this may be in vain. __小题4:_ When a suspect leaves finger-prints behind at the scene of a crime, they are difficult to detect(察觉) with the naked eye. __小题5:__ Some of the marks found are incomplete but identification is possible if a print of a quarter of an inch square can be obtained.
A．Special techniques are used to “develop” them.
B．A fingerprint is an impression of the friction ridges of all part of the finger.
C．It is only when the inner skin is injured that the arrangement will be destroyed.
D．With special methods, identification can be achieved successfully within a short time.E. A latent(潜在的) print is the chance reproduction of the friction ridges deposited on the surface of an item.
F. His finger-prints can prove who he is even if his appearance has been changed by age or accident.
G. Every human being has a unique arrangement of the skin on his fingers and this arrangement is unchangeable.