The symbol ∽ indicates negation or the opposite. If true, then its negation will be false.
Let's complete column 3 first which is ∽s.
As you can see in the table above, the answers in column 3 is are the opposites of column 2.
On the other hand, the symbol ⋀ means "and". The result is TRUE if and only if both propositions are true.
So, to answer the fourth column, here is the table:
As seen in the table above, the only TRUE value is when r is true and ∽s is true which is found in the second row.
