🚀 go-pugleaf

I think this is a neat folder to discuss topics on cyptography.
I am currently doing a course on it and there are some questions 
on my mind.Can anyone help?

Does anyone know how to prove the following :

Q1 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Definition : M = the message space
             K = the key space
             C = the cytogram space 
 ! ! means the cardinality of

Given that !M! = !K! = !C! then perfect secrecy is achieved if

(1) all the keys are equiprobable
(2) there is exactly one transformation ( i.e one key ) from a given
    message to a given cyptogram

Q2 ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

how can the key space be increased by using a combination of keys are
encryption instead of a single key replacement?
i.e instead of A   ......  B
               .          .
               .          .
               .          .
               .          .
               Z           K

to try        AB  .......   CD
               .          .
               .          .
               .          .
               .          .
              AZ   ......   WE  ...etc
 
Thanks in advance !!!!!

Linda