Give other instances of argument forms 3-4 that are not valid. Explain why these instances are invalid and why they show that the general argument form is invalid.
1. $\sim X \vee Y$
2. $\sim(X \vee Y)$
3. $\sim(Z \vee Z)$
4. $\sim(Z \vee \sim Z)$
5. $\sim \sim(A \vee B)$
6. $(A \vee Z) \& B$
7. $(A \vee X) \&(B \vee Z)$
8. $(A \& Z) \vee(B \& Z)$
9. $\sim(A \vee(Z \vee X))$
10. $\sim(A \vee \sim(Z \vee X))$
11. $\sim A \vee \sim(Z \vee X)$
12. $\sim Z \vee(Z \& A)$
13. $\sim(Z \vee(Z \& A))$
14. $\sim((Z \vee Z) \& A)$
15. $A \vee((\sim B \& C) \vee \sim(\sim B \vee \sim(Z \vee B)))$
16. $A \&((\sim B \& C) \mathrm{n} \sim(\sim B \vee \sim(Z \vee B)))$