Computer Security Homework $2($Due Friday $9/1/23)$

$1.$ Encrypt the message CY with a one$-$time pad whose key is $(3,4)($or equivalently $$DE$).$

$2.$ The message RAIN was encrypted with a one$-$time pad into RRHG$.$ You obtain the ciphertext HRHE of

another message encrypted with the exact same key. What must that message say? Show your work.

$[$Hint: The text should decrypt into readable English.$]$

$3.$ Use columnar transposition with the key $[2,4,1,3]$ to encrypt the message

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