Exercise B

Use complete or partial truth tables (as appropriate) to determine whether these sentences are jointly satisfiable, or jointly unsatisfiable:

1. $A\wedge B$, $C\rightarrow\neg B$, $C$

2. $A\rightarrow B$, $B\rightarrow C$, $A$, $\neg C$

3. $A\vee B$, $B\vee C$, $C\rightarrow\neg A$

4. $A$, $B$, $C$, $\neg D$, $\neg E$, $F$