Let W denote the set of English words. For u,v ? W, declare u ? v providedthat u, v have the same length and u,v have the same first letter and u, vhave the same last letter.
a) Prove that ? is an equivalence relation.
b) List all elements of the equivalence class [a]
c) List all elements of [ox]
d) List all elements of [are]
e) List all elements of [five]. Can you find more than 15?
f) Bonus. Find all three letter words x such that[x] has 5 elements.
