(a)
(labelled-posn-label (first (rest (rest lolp))))

(labelled-posn-label (first (rest (rest (cons (make-labelled-posn (make-posn 0 0) ¡¯Origin)
(cons (make-labelled-posn (make-posn 5 10) ¡¯Five-n-dime)
(cons (make-labelled-posn (make-posn ?200 0) ¡¯Campus)
empty)))))))

(labelled-posn-label (first (rest (cons (make-labelled-posn (make-posn 5 10) ¡¯Five-n-dime)
(cons (make-labelled-posn (make-posn ?200 0) ¡¯Campus)
empty)))))

(labelled-posn-label (first (cons (make-labelled-posn (make-posn ?200 0) ¡¯Campus)
empty)))

(labelled-posn-label (make-labelled-posn (make-posn ?200 0) ¡¯Campus))

¡¯Campus


(b)
(posn-y (labelled-posn-posn (first (rest lolp))))

(posn-y (labelled-posn-posn (first (rest (cons (make-labelled-posn (make-posn 0 0) 'Origin)
(cons (make-labelled-posn (make-posn 5 10) 'Five-n-dime)
(cons (make-labelled-posn (make-posn -200 0) 'Campus)
empty)))))))

(posn-y (labelled-posn-posn (first (cons (make-labelled-posn (make-posn 5 10) 'Five-n-dime)
(cons (make-labelled-posn (make-posn -200 0) 'Campus)
empty)))))

(posn-y (labelled-posn-posn (make-labelled-posn (make-posn 5 10) 'Five-n-dime)))

(posn-y (make-posn 5 10))

10