(define (get-n n sent)
  (if (= n 0) (first sent)
      (get-n (- n 1) (butfirst sent))))



(define (expt base power)
  (if (= power 0) 1
      (* base (expt base (- power 1)))))



(define (repeat n fn)
  (if (= n 0) 
    (lambda (arg) arg)
    (lambda (arg)
         (fn ((repeat (- n 1) fn) arg)))))


(define (get-n n sent)
  (first ((repeat n butfirst) sent)))


(define (expt base power)
  ((repeat power (lambda (x) (* x base))) 1))