Exercise 4.55.  Give simple queries that retrieve the following 
information from the data base:

a. all people supervised by Ben Bitdiddle;

b. the names and jobs of all people in the accounting division;

c. the names and addresses of all people who live in Slumerville.

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(supervisor ?x (Bitdiddle Ben))

(job ?x (accounting . ?y))

(address ?x (Slumerville ?y ?z))