#| BEGIN (Write your solution here) |#
(define (stream-map proc . argstreams)
  (if (or (null? argstreams)
          (ormap stream-null? argstreams))
      the-empty-stream
      (cons-stream
       (apply proc (map stream-car argstreams))
       (apply stream-map
              (cons proc (map stream-cdr argstreams))))))
#| END |#