3. Caesar Cipher (1) You are given a message halloween and a key 4, please encrypt it with Caesar Cipher and show the Ciphertext. Note: We normally use lower case letters to represent plaintext and capital letters to represent ciphertext. (2) Suppose that you have intercepted a message encrypted using Caesar cipher. The ciphertext is OQTPKPI. Please find the key using the brute-force method, and show the plaintext.. Hint: You can convert the letters to the numbers like A>1,B>2,Z>26, then try to subtract each number in the ciphertext by the key value ( k=1,2.).F oreachresult, convert the numbers into letter and check whether it is a meaningful word or sentence..