bind ; symbolic names to expressions
(define pi 3.1415927)
(define two_pi (* pi 2))
; define a cube function
(define (cube x) (* x x x))
; use map to apply nameless function to values
(map (lambda (x) (* x x x)) '(2 3 4 5))
; use map to apply cube function to values
(map cube '(2 3 4 5))
; predicate functions end in ?
(zero? 10 (- 10))
(zero? (* 2 3))
(even? (* 4 8))
; define a function and use COND
(define (lettergrade g)
(cond
((>= g 90) (display "A\n"))
((>= g 80) (display "B\n&qu...