Cryptography: $(1$ point$)$ This question concerns block cipher modes. We will use a simple affine cipher, which can be expressed in C as follows.

char cipher$($unsigned char block, char key$)$

$\{$

return $($key$+11*$block$)\%256$;

$\}$

Note that the block size is $8$ bits, which is one byte $($and one ASCII character$).$ We will work with the fixed key $008.$

corresponding ASCII code.

a$)$ Encrypt the plaintext "brownish" using CTR mode. Please enter your answer in hex. $($Please do enter an $0$x$,$ as this has been done.$)$

$0x$

b$)$ Encrypt the plaintext "bangs" using ECB mode. Please enter your answer in hex.

$0x$

c$)$ Encrypt the plaintext "dangling" using CF B mode. Please enter your answer in hex.

$0x$

d$)$ Encrypt the plaintext "long $"$ using $CBC$ mode. Please enter your answer in hex.

$0x$

e$)$ Encrypt the plaintext "lowering" using OFB mode. Please enter your answer in hex.

$0x$