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07 - Caesar cipher

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

  Julius Caesar

  Cesare Lattes

  Caesar Pelli

  Caesar Frank

 2. The Caesar cipher is also known as …

  the spacial cipher

  the shift cipher

  the one up cipher

  the follow on cipher

 3. What type of cipher is the Caesar cipher?

  An unbreakable cipher

  An exchange cipher

  A polyalphabetic cipher

  A substitution cipher

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

  FALSE

  TRUE

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

  guard

  entry

  lock

  key

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

  JGNNQ YQTNF

  JGNNQ XPSME

  JGNNQ ASVPH

  JGNNQ YQTOG

 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.

  TRUE

  FALSE

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

  DOOR OPENS OUTWARDS

  MEET ME AT THE BRIDGE

  HOW THIS TIME PASSES

  GOOD TO BRING PARCEL

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

  FALSE

  TRUE