2. (15 marks) Consider the language that contains the predicates of symbols degree, student, pass, test, goodscore, and subscribe, all of arty 0 . Given the following knowledge base built from this language: degreestudentpass.passtestgoodscore.testsubscribe.student.subscribe. (a) (5 marks) How many interpretations exist for this propositional language? (b) (5 marks) Consider the following interpretations: 1 Which interpretations are models of the knowledge-base? Which are not? Why (not)? (c) (5 marks) Give all logical consequences of the knowledge-base