1. What is the common theme behind these two papers?

2. What is the difference between these two papers?

3. What is the goal of compositional reasoning?

4. What's the relationship between the <= relation used in section 3
   of the Tahar survey and our abstraction paper from last week? 

5. Consider our original highway/farm traffic light.  Assume we wanted
   to treat the light in each direction as a separate component.  How
   would you decompose the property AG ((farm=red and car_present) ->
   AF farm=green) into properties about each component?

6. Is assume-guarantee reasoning easier in CTL or LTL (or about the
   same in each)?  Justify your answer (with concrete details about
   what makes the reasoning easy or hard).

7. The Fisler et al. paper uses CTL.  Could they have used LTL with
   the same methodology?  Why or why not?

8. Evaluate the forms of compositional reasoning presented in these
   papers from the perspective of a designer who wishes to use
   verification: what are the strengths and weaknesses of each
   approach?  Which do you see as viable in practice?