The author of PS9 makes the point that exception classes can be trivial a. Illustrate this point by declaring a complete class specification for a C++ NoSuchSubreddit exception. You should have no difficulty confining your answer to the tiny space given here: b. Slightly more subtle is this: if the class specification is so trivial, what good it is? Why even declare such a class at all? Be very specific and precise in your answer, but keep it short