TEST BANK FOR Introduction to cryptography with coding theory 2nd Edition By Wade Trappe, Lawrence C. Washington Converted

1. Among the shifts of EVIRE, there are two words: arena and river. Therefore, Anthony cannot determine where to meet Caesar. 2. The inverse of 9 mod 26 is 3. Therefore, the decryption function is x = 3(y−2) = 3y−2 (mod 26). Now simply decrypt letter by letter as follows. U = 20 so decrypt U by calculating 3 ∗ 20 − 6 (mod 26) = 2, and so on. The decrypted message is ’cat’. 3. Changing the plaintext to numbers yields 7, 14, 22, 0, 17, 4, 24, 14, 20. Applying 5x+7 to each yields...