Exercise 1: Eve is given the ciphertext 'ECLEHLPQNGYPLLPALIETQDUWQRFATOAULPQVGLHDEWVEFQLEVEFQ' and the inform- ation that the plaintext is in English and encrypted with the 26-character multiplicative cipher. a) Apply frequency analysis to the ciphertext and find the key ki- [4 marks] b) Using the key k identified in a), find all the plaintext-ciphertext pairs of letters (p. c) in the English alphabet such that k-p=c mod 26. Create a table that lists all the plaintext-ciphertext pairs. [2 marks] c) Use the table of plaintext-ciphertext pairs to decipher the message in a) and find the plaintext. [2 marks] Exercise 1: Eve is given the ciphertext 'ECLEHLPQNGYPLLPALIETQDUWQRFATOAULPQVGLHDEWVEFQLEVEFQ' and the inform- ation that the plaintext is in English and encrypted with the 26-character multiplicative cipher. a) Apply frequency analysis to the ciphertext and find the key ki- [4 marks] b) Using the key k identified in a), find all the plaintext-ciphertext pairs of letters (p. c) in the English alphabet such that k-p=c mod 26. Create a table that lists all the plaintext-ciphertext pairs. [2 marks] c) Use the table of plaintext-ciphertext pairs to decipher the message in a) and find the plaintext. [2 marks]