[Haskell-beginners] problem 8 / 9 chapter 4, RWH

[Michael Litchard]

I noticed that in problem 4, the use of Either is needed, which hasn't
been introduced yet. I've gotten stuck on 8/9, and am wondering if
there
is something needed that hasn't been introduced yet as well?

Put another way, can problem 8/9 be done given the parts of the
language introduced thus far?


Regards,
               Michael Litchard