a) Using the symbols one and two and the procedure cons, we can construct the list (one two) by typing (cons 'one (cons 'two ' ( )). Using the symbols one, two, three, and four and the procedure cons, construct the following lists without using quoted lists (you may use quoted symbols and the empty list): (one two three four) b) Enter (2 1). What is the returned message? c) Enter' (21) What does the quote do? d) We can extract the symbol a from the list (b (a c) d) using car and cdr by going through the following steps: (cdr(b(ac)d))((ac)d) (car(cdr(b(ac)d)))=>(ac) (car(car(cdr(b(ac)d))))=>a For each of the following lists, write the expression using car and cdr that extracts the symbol a: (b a c d) ((b d) (c a))