Consider the following encryption scheme to provide confidentiality. A wants to send a message M to B. A calculates X, the ASCII representation of todays date. A then XORs M with X to get the ciphertext C. When B receives C, he XORs C with X to get M. You can assume that the number of bits in M is no more than the number of bits in X. Is this a good scheme? Give a YES/NO answer. If you said NO, explain your answer i.e. explain what you think is the single biggest weakness of the scheme.