A Prolog database contains the following, where boss(X, Y ) means X is Ys boss and supervisor(X, Y ) means X is Ys supervisor:

boss(mike, joan) boss( judith, mike) boss(anita, judith) boss( judith, kim) boss(kim, enrique) boss(anita, sam) boss(enrique, jefferson) boss(mike, hamal) supervisor(X, Y ) 6= boss(X, Y ) supervisor(X, Y ) 6= boss(X, Z ) and supervisor (Z, Y )

Find the results of the following queries: a. ?boss(X, sam) b. ?boss( judith, X ) c. ?supervisor(anita, X )