2 points were given if the relationship between the interpretations were correct but the sentence given did not distinguish them. Full credit was given if existential quantifiers were used. The sentence given was considered incorrect if variables were assigned elements in the domain under which the sentence would be true or false because the question asked for simply a sentence in relational logic - not a sentence and a variable assignment. Let S and T be sets of sentences, and let phi and t be sentences in relational logic. State whether each of the following statements are true or false.
T entails phi False.
If the intersection is empty, for example. Each of the 6 parts was worth 1.5 points. Since this adds up to nine, every student was given a one point free-be. This is a model for all three sentences. The above variable assignment makes the sentence false.