Please solve the below questions. Q1) a-What is the significance of using only

Please solve the below questions.
Q1)
a-What is the significance of using only 5 x 5 matrix?
b-What is the criteria of selecting which letter to add to the plaintext to make it even number of characters?
c-What is the weakness of playfair cipher?
d-Given the Keyword and the cipher text generated using playfair cipher, find the plain text. Show all the steps.
Keyword : CIPHER
Cipher text : RGXHUQOGBIDHNZMFDKFUQDSX
f-Encrypt the above plain text using Double playfair technique with any two keywords of your choice. Show all the steps. Give the keywords along with your answer. [10 Marks]
Q2)
a-Write 5 differences between Substitution cipher and Transposition Cipher.
b-Encrypt the given plaintext using columnar transposition cipher and 4 columns. Show all the steps.
“TRY NOT TO GET HACKED”
c-Write the mathematical function of Affine Cipher. Encrypt the text “ZERO DAY ATTACK” with the key (9,7) using Affine cipher. Show all the steps.