Example: one Auto argument

;; Purpose and Contract:
;; determine whether an auto can travel the desired distance on one tank of gas
;; Auto Number -> Boolean
;; (define (reach? a dist)

;; Examples:
;; (reach? auto1 200) "should be" true
;; (reach? auto1 320) "should be" false
;; (reach? auto2 200) "should be" false

;; Template:
;; ... (auto-model a) ...
;; ... (auto-tank-size a) ... 
;; ... (auto-mpg a) ...

;; ... (auto-range a) ...

;; Program:
(define (reach? a dist)
  (< dist (auto-range a)))

;; Tests
(equal? (reach? auto1 200) true)
(equal? (reach? auto1 320) false)
(equal? (reach? auto2 200) false)