Suppose p is a contradiction q is a tautology and r is a con
 Suppose p is a contradiction, q is a tautology, and r is a contingent sentence. Which of the following are true? 
 A) r, therefore q is an invalid argument
 B) p,therefore r is a valid argument
 C) q unless r is a tautology
 D) r, therefore p is an invalid argument
 E) p, therefore q is an invalid argument
  Suppose p is a contradiction, q is a tautology, and r is a contingent sentence. Which of the following are true? 
 A) r, therefore q is an invalid argument
 B) p,therefore r is a valid argument
 C) q unless r is a tautology
 D) r, therefore p is an invalid argument
 E) p, therefore q is an invalid argument
 A) r, therefore q is an invalid argument
 B) p,therefore r is a valid argument
 C) q unless r is a tautology
 D) r, therefore p is an invalid argument
 E) p, therefore q is an invalid argument
Solution
B and C

