(define pi 3.141592654)

(define (square-area r) (* r r))

(define (circle-area r) (* pi r r))

(define (sphere-area r) (* 4 pi r r))

(define (hexagon-area r) (* (sqrt 3) 1.5 r r))


;;;;;;;;;;;;;;;;;;;


(define (area shape r) (* shape r r))

(define square 1)
(define circle pi)
(define sphere (* 4 pi))
(define hexagon (* (sqrt 3) 1.5))


;;;;;;;;;;;;;;;;;;;


(define (sumsquare a b)
  (if (> a b)
      0
      (+ (* a a) (sumsquare (+ a 1) b)) ))

(define (sumcube a b)
  (if (> a b)
      0
      (+ (* a a a) (sumcube (+ a 1) b)) ))