Exercise 1: Decrypting an Unknown-Shift Caesar Cipher — Possible Solution
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Ciphertext: WKLV LV IXQ

Approach: with only 25 possible shifts, brute force is completely
practical by hand — try every shift from 1 to 25 and see which one
produces readable English.

Shifting back by 3 (i.e. treating the ciphertext as if it were
encrypted with shift +3, so decrypting means shifting each letter
back by 3):

W -> T
K -> H
L -> I
V -> S

L -> I
V -> S

I -> F
X -> U
Q -> N

Result: THIS IS FUN

Shift amount: 3 (the same shift used in this chapter's own
HELLO WORLD -> KHOOR ZRUOG example).

Plaintext: THIS IS FUN

WHY THIS WORKS AS AN ANSWER
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Because Caesar's keyspace is only 25 possible shifts, there was no
need for frequency analysis at all here — trying every shift and
recognizing "THIS IS FUN" as valid English on shift 3 is both
faster and more certain than a statistical approach would be for such
a short message. This is exactly the point the chapter's own
warn-box makes: a 25-key keyspace is not a real defense, because
brute force alone is sufficient.