Any help is appreciated , I am working on a practice review for my class.

Consider the following university data base, which has a department relation (depttown says that Kworks in department y, note that Wolnt appointments are possible), a chair relation (chair(x, y) says that the chair of department x), and a rank relation (rankux.y. Says that has rankv.and earns salary dept(newton, physics) deptlchurch, compsci- full, 45. dept(newton, math). ranktturing, assist, 201 dept(einstein, physics). deptferdos, math). dept feynman, physics). rank(babbage, assists, 23- dept(von Neumann, compsci). rankleuler, assoc, 401- chair physics, newton) dept(turing, math rank(church assoc 40) chairtmath, euler). dept(turing, compsc). chair(compsci, vonNeumann). rankleinstein, full 45). rank(Meryeman, assoc. ss). dept(babbage, compsci). full, 35). dept(euler, math). rank(erdos, assoc, 25). a) What are all the possibl e answers to the query: rank assoc -l de math b) what query would you ask to get the names and ranks of department chairs. (x is considered to be a colleague ofx). d) The boss relation, boss(x,y) says thatxis the chair of the department that yis in. Write a rule to define the boss relation. e) A professor is highl d if he earns the same or more than his chair. Write a rule to define the highlypaid predicate eel