USE THE FOLLOWING SENTENCES. (DO NOT USE ANY OF THE NUMBERED SENTENCES IN EXERCISE 3-4.) RUN EACH OF THE TWO SENTENCES BELOW THROUGH ALL OF THE SENTENCE FORMS ON THE RHS OF EXERCISE 3-4. LIST THE LETTERS FOR WHICH EACH OF THE TWO SENTENCES BELOW IS A SUBSTITUTION-INSTANCE. (---> means 'if ... then ...' It is the horseshoe. * means 'and.' It is the dot.)

1. ~~[(A v ~A) v ~ ~B]

2. ~~A --> ~ (~B --> C)

a. p

b. ~ p.

c. pva

d. pa

e. ~ pva f. ~pa

g. ~p ~9

h. ~ (pva)

i. ~ (p 9)

j. ~(~ p a)

k. (pv q) Dr

l. pv ( gr)

m. ( pv q) Dr

n. ~ (pv q) D

r 0. (pvq)~r

p. ~[pv (q) r)]

q. ~[(pv q) > r]