Let game(ball, rugby) be true if the ball is used in rugby and false otherwise.
Let shape(ball, round) be true if the ball is round and false otherwise.
Consider the following logical sentences :
s1: ∀ball ¬ game(ball, rugby) ⇒shape(ball, round)
s2: ∀ball ¬ shape(ball, round) ⇒game(ball, rugby)
s3: ∀ball game(ball, rugby) ⇒ ¬shape(ball, round)
s4: ∀ball shape(ball, round) ⇒ ¬ game(ball, rugby)
Which of the following choices is/are logical representations of the assertion,
“All balls are round except balls used in rugby”?