$1)$ Explain the meet$-$in$-$the$-$middle attack.

$2)$ Compare and contrast E C B$,$ C B C$,$ C F B$,$ O F B$,$ and counter modes of operation.

$3)$ Present an overview of the X T S$-$A E S mode of operation.

$4)$ Compare and contrast FF$1,$ FF$2,$ and FF$3$ format$-$preserving Encryption.

$5)$ Is it possible to perform encryption operations in parallel on multiple blocks of plaintext in CBC mode? How about Decryption? Explain.

$6)$ In the discussion of CTR mode, it was mentioned that if any plaintext block that is encrypted using a given counter value is known, then the output of the encryption function can be determined easily from the associated ciphertext block. show the calculation.

$7)$ In discussing OFB, it was mentioned that if it was known that two different messages had an identical block of plaintext in the identical position, it would be possible to recover the corresponding Oi block. Show the calculation.