Exercise 2.26: Suppose we define x and y to be two lists:
(define x (list 1 2 3))
(define y (list 4 5 6))
What result is printed by the interpreter in response to evaluating each of the following expressions:
(append x y)
(1 2 3 4 5 6)
(cons x y)
((1 2 3) 4 5 6)
(list x y)
((1 2 3) (4 5 6))