Explain Diffie$-$Hellman key exchange algorithm and solve the

following scenario: In the Diffie$-$Hellman key exchange, users

A and B agree on a common prime q$=11$ and a primitive root

a$=8.$ If user A$\text{'}$s public key is YA$=5,$ what is the corresponding

private key XA$?$ Similarly, if user B$\text{'}$s public key is YB$=4,$ what

is the corresponding private key XB$?$ What is the value of the

shared secret key between A and B$?$