Assume the following mapping table for the representation of alphabets:

Alphabet	A	B	C		X	Y	Z
Number	0	1	2	..	23	24	25

1. Assume a key K=9. Encrypt HELLOWORLD with the key and Break the code: UXENBNLDARCH. Give the key and decoded message (plaintext). The decrypted message should be human readable. b.
2. In cryptography, encryption is defined C = E(M), where M is the plaintext, C is the associated ciphertext, and E() is the encryption function. When assuming a key K, a nave definition for Caesar cipher encryption would be C = E(M) = (M+K), but it actually does work well for some messages. Correct the encryption function.