(define WIDTH 600)
(define SHEEP-0  (make-sheep 0 MATHEXPR-0 5))
(define SHEEP-1  (make-sheep (/ WIDTH 2) MATHEXPR-1 5))
(define SHEEP-2  (make-sheep WIDTH MATHEXPR-2 5))


(define LOS-0 '())
(define LOS-1 (cons SHEEP-0 LOS-0))
(define LOS-2 (cons SHEEP-1 LOS-1))
(define LOS-3 (cons SHEEP-2 LOS-2))

(define WORLD-0 ("" LOS-3 0))
(define WORLD-1 ("90" LOS-3 1))
(define WORLD-2 ("" LOS-0 4))