big-bang 03

Part A

Setup:

(define (draw-h-a c)
  (overlay (circle 100 "solid" c)
           (square 80 "outline" "black")))
(big-bang (make-color 0 0 250)
  (on-draw draw-h-a 210 180) ;; little new thing?
  (on-mouse minnie-a))

1. What “kind of thing” is the model? (Same question, restated: what is the type of the model?)
2. What is the signature of draw-h-a?
3. What is the name and signature for the mouse handler?
4. Write a check-expect for the mouse handler that shows that when the old model is (make-color 0 0 250) and you move the mouse to coordinates (80, 130), the new model is (make-color 80 255 255).
5. Make up another check-expect for the mouse handler, guessing its purpose from the first example.