Which of the sentences in (1)-(5) are entailed by (1)? Why? Which of the sentences in (1)-(5) are presupposed by (1)? Why? For each sentence S in (1)-(5) that is not entailed by (1), describe a context where (1) is true and S is false. Your contexts should be specific, and their descriptions should avoid the words only and every. (Assume 'pass' = 'not fail'.) (1) Only the professor doesn't know why every student passed the exam. (2) Every student passed the exam. (3) Some student failed the exam. (4) Everyone who is not the professor knows why every student passed the exam. (5) Some student failed the exam or everyone who is not the professor knows why every student passed the exam.