In coming colour codes for BT phone wiring domestic

Question

In coming colour codes for BT phone wiring domestic

Answer 1

white and blue to 2

blue and white to 5  

Answer 2

For 4 core

2 connect to Green&White / 3 to Orange&White/4 to White&Orange/

5 to White&Blue

For 6 core

As for 4 core plus: 1 connect to Green&White/ 6 toWhite&Green

Answer 3

Standard wiring and terminal numbers are:

2 = Blue/white

3 = Orange/white

4 = White/orange

5 = White/blue

Or are you referring to the colors on the drop wire which comes from outside the house to the master jack?

On the standard dropwire used in modern BT installations the first line is connected:

A = Orange

B = White

(A terminal goes through to #5, B terminal to #2).

The green (A) and black (B) wires are used if you have a second line, or if the first pair goes faulty, etc.  

The multiple yellows are just strengthening wires, not used for the actual phone line connections.