(10 points) Alice and Bob share the same pair of symmetric encryption algorithms, E and D. Also, they share the symmetric encryption key K. Suppose Alice wants to send a message M to Bob. Design an encryption scheme that will protect the confidentiality of M and prevent the message tampering during the transmission. (Hint: You may need to use cryptographic hash HASH to create a digest for some messages. For example, you can generate a digest for message D with HASH(D). You can concatenate two messages by using concatenate operator "II". For example, you can concatenate two message A and B with AB). a) (5 points) Write down the message format sent from Alice to Bob