1. Name 2 examples of artificial intelligence other than recognizing 
spam mail and Eliza.

2. Draw a simple binary graph illustrating the decision-making of the 
spam filter on page 129 of the text.

A simple binary graph is when each node has two children. Binary graphs
 are good for scenarios where there is an "either or" situation - e.g.
 whether something is "yes" or "no, or whether an organism is an animal
 or a plant. In the latter case, the organism will be a node that has 
two child nodes - animal in one and plant in another. All animals are 
mammals or non-mammals. So you can further divide the animal node. When
 appropriate, also give a selection criteria (e.g. an organism that can
 make noise is an animal, and one that can't is a plant) on the graph.

	 organism
	   /	\
can make  /	 \ cannot make noise
noise	 /	  \
    animal	plant

3. What are the three disadvantages of using the if-then-else algorithm
 to identify spam?

4. In your own words, describe how the alternative algorithm on page 131
 sorts junk mail.