1. Describe how an attacker can obtain the one-time pad that is used to encrypt a message, given both the message and the ciphertext, and explain why your method works.
2. Suppose that two equal-sized messages M₁ and M₂ are encrypted with the same one-time pad and let C₁ and C₂ be the resulting ciphertexts. Suppose further that an attacker captures both ciphertexts C₁ and C₂, and knows one of the two messages, say M₁. Based on Part a), describe how the attacker can obtain the other message M₂, and explain why your method works.
3. Lets think about a more realistic situation than part b) that the attacker captures both ciphertexts C₁ and C_2, but does not know message M_1. Based on part b), can you provide an example showing that the attacker can still obtain the message M₂ ? You can do research online and find approaches. By answering this question, you can have an idea on how an attacker can do in practice and why the one-time pad cannot be used more than once.