more virtual functions


administrative notes
  Midterm 2 returned; answers posted on web
  HW 4, Part I will be returned Thu.
  HW 5 will be released Tue.
    Read instructions---Don't make your lives unnecessarily difficult.
    short written part due Thu.
    final due date, a week from Thu., 10:00 pm 
  newsgroup...use it!


misc. bits of information
  virtual destructors
  short method defs. in header
  default param. values
  further remarks on cake, mmmmm
    base class:  cheesecake
    derived class:  mocha strawberry cheesecake


pure virtual functions