SGT

1

2 - shift is 13 3 - same as shift of 13 4 - N is a shift of 13, key repeats 5 - same as 4, repeated key 8 - true, value of A is 0, no effect

1 - shift is 22 3 - equivalent of shift of 22

No, both 4 gives ARENA, 13 gives RIVER, so they cannot decide.

No, information is lost Encryption function is not a bijection

Begin by constructing 5x5 grid:

C E G O V H S I / J P W A B K Q X R D M T Y L F N U Z

Text to encrypt: “MEET ME AT HAMMERSMITH BRIDGE TONIGHT” Using the filler $X$

ME	ET	ME	AT	HA	MX	ME	RS	MI	TH	BR	ID	ME	TO	NI	GH	TX
GD	DO	GD	RQ	AR	KY	GD	HD	NK	PR	DA	MS	OG	UP	GK	IC	QY

Keyword: RELATIONS Plaintext: TO BE OR NOT TO BE THAT IS THE QUESTION

key plaintext ciphertext R T K E O S L B M A E E T O H I R Z O N B N O B S T L R T K E O S L B M A E E T T M I H P O A O N T G S I A R S J E T X L H S A E E T Q J I U C O E S N S F S T L R I Z E O S L N Y

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