15. Practice All

Do all of this work in a single Racket file. You need to turn this assignment in on classroom. You may attach your solution file or copy and paste the code as a private comment and mark the assignment complete.

Read Section 15.6 (Unnecessary conditionals) to review how to simplify. (PDF page 230ff.)

Note to book readers: I disagree with the author about section 15.7 (nested conditionals) so I suggest not reading it. If you need to put conditionals inside of conditionals, make a helper function.

1. Simplify:

(define (mess-1 in-bed? alarm-time clock-time)
  (cond [(boolean=? in-bed? true)
         (cond [(< clock-time alarm-time)
                "sleep"]
               [else
                "wake up"])]
        [(boolean=? in-bed? false)
         "wake up"]))

2. Simplify:

(define (ice-danger? temp precipitation? salt?)
  (and (boolean=? true precipitation?)
       (boolean=? false salt?)
       (not (>= temp 32))))

3. Book problem 15.5.1, page 218 (pdf page 229): carpet-price.

4. Book problem 15.5.2, page 218 (pdf page 229): digital-thermometer.

5. Book problem 15.5.4 (who-won) and 15.5.5 (4-votes->winner), page 219 (pdf page 230).

6. There are three circles of radius 150 drawn on a 500x500 background. The centers are red (250,325), green (175,175), and blue (325,175). Make the area where circles overlap have all of the colors from the circles, so where red and green overlap the color is (make-color 255 255 0).