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07 - Caesar cipher

 1. Who is the Caesar cipher named after?
caesar_q1.jpg

  Caesar Frank

  Caesar Pelli

  Cesare Lattes

  Julius Caesar

 2. The Caesar cipher is also known as …

  the spacial cipher

  the shift cipher

  the follow on cipher

  the one up cipher

 3. What type of cipher is the Caesar cipher?

  A polyalphabetic cipher

  An exchange cipher

  An unbreakable cipher

  A substitution cipher

 4. The Caesar cipher replaces each plaintext letter with another letter a fixed position further in the alphabet.

  TRUE

  FALSE

 5. The distance between each plaintext and ciphertext letter is the …

  entry

  lock

  guard

  key

 6. If the Caesar cipher shift is two, how would HELLO WORLD appear in ciphertext?

  JGNNQ XPSME

  JGNNQ YQTNF

  JGNNQ YQTOG

  JGNNQ ASVPH

 7. What is the most frequently used letter in the English language?

  A

  E

  N

  O

 8. Letter frequency can often be used to break a Caesar cipher as the shift is the same for each letter.

  FALSE

  TRUE

 9. Using frequency analysis, what is the most likely plaintext of RJJYRJFYYMJGWNILJ?

  MEET ME AT THE BRIDGE

  GOOD TO BRING PARCEL

  DOOR OPENS OUTWARDS

  HOW THIS TIME PASSES

 10. The ROT13 algorithm is an example of a Caesar cipher.

  FALSE

  TRUE