$1)$ If the private key is $(3,33).$

What is the plain text if the encrypted text is $7?$

$2)$ If the public key is $(7,33),$ what is the encrypted value if the message is the number $2.$

$3)$ If we start by p$=3$ and q$=11$:

a$)$ Give a public key.

b$)$ What are the possible values of e

c$)$ What are the possible values of d$.$

d$)$ Suggest a private key.

$4)$ Speaking about the Diffie$-$Hellman algorithm, given these numbers:

P$=13$

G$=6$

Alice Private $=5$

Bob private $=4$

a$)$ What is the exchanged public key by Alice $($number will be sent to Bob$).$

b$)$ What is the exchanged public key by Bob $($number will be sent to Alice$).$

c$)$ What is the key used for communication between Alice and Bob.