1. Suppose that the following 128-bit AES key is given in hex: 0000 0000 0000 0000 0000 0000 0000 0000. Write the first four subkeys computed according to the AES key schedule.

2. Let the 128-bit AES with key from Problem 1 (all-zero key) be used for encrypting the all-zero message block, i.e, 0000 0000 0000 0000 0000 0000 0000 0000 in hex. Write the resulting ciphertext.

3. Let a ciphertext (with at least 4 blocks) be constructed using the CBC mode. is transmitted with error in one of the bits (assuming that ). How many blocks of the plaintext will be decrypted incorrectly? Explain your answer.