The strings below are the rst 50 or so characters of ciphertext strings of more than 1000 characters. Each string is one of the following:

The strings below are the first 50 or so characters of ciphertext strings of more than 1000 characters. Each string is one of the following: random strings, transposition ciphers, affine ciphers applied to English text. Below each string are the frequencies of the 10 most common letters in the ciphertext.

A). OVATUHOAOVEETPTEALEICTHAOICDAOETTIAAOENIIIFWALTILAEGES e .14 t .10 a .08 o .08 h .07 r .07 n .07 i .06 d .05 s .04 (2, .086)

B). TUMDGKUDQERNGQPQRYQEDGEWUUMDTEJZQDGHDUMWZJTUDJZU q .14 j .11 e .08 u .08 z .07 d .07 r .07 c .06 n .05 g .04 (12, .093)

C). FZYDUPKLWHRWEUZMWSDZHWKRMTWKBAMLRTGGSXKQAUONMJV m .06 x .06 w .06 t .05 j .05 k .04 o .04 s .04 l .04 n .04 (3, .047)

D). SZQRCRJZQKUMDGQUTZMOERQPQRJGCJHQKUOQGRQKQGGEDYTUDU q .15 j .11 r .08 e .07 u .07 g .07 z .07 c .06 d .06 l .04 (23, .083)

Use this data to answer the following. EXPLAIN YOUR REASONING. The points credited for your solutions increase as the evidence you provide for your conclusions increases. Use the back of the previous page if you need more room.

a). Which string is a random string of letters? Explain.
b). Identify which ciphertexts are the result of a transposition cipher. Carefully explain your reasoning.
c). Two ciphertexts are different plaintexts encrypted by an affine cipher with the same key. Which are they? Explain.