(define (upper-bound x) (cdr x)) (define (lower-bound x) (car x)) (define (sub-interval x y) (make-interval (- (upper-bound x) (lower-bound y)) (- (upper-bound y) (lower-bound x))))

(define (make-interval a b) (cons a b)) (define (upper-bound x) (if (> (car x) (cdr x)) (car x) (cdr x))) (define (lower-bound y) (if (< (car y) (cdr y)) (car y) (cdr y)))

(define zero (lambda (f) (lambda (x) x))) (define (add-1 n) (lambda (f) (lambda (x) (f ((n f) x))))) (add-1 zero) (lambda (f) (lambda (x) (f (((lambda (f) (lambda (x) x)) f) x)))) (lambda (f) (lambda (x) (f ((lambda (x) x) x)))) (lambda (f…