Outline:

1. Recap Lesson 8
   • Exercise 1
2. Functions and variable scope
   • Exercise 2
3. Making choices
   • Boolean expressions in Python
   • Exercise 3
   • Two-way decisions: if/else
   • Exercise 4

Explore after class:

4. Practice with functions:
   • functions that return multiple values: Exercise 5
   • functions that modify their parameters: Exercise 6
5. Error handling with conditional code: Exercise 7

Reading assignment (to be completed by the next class):

• Zelle sections 6.6-6.8 (pp. 193-203)
• Zelle sections 7.1-7.2 (pp. 209-220)
• Assignment #4 (due next Thursday at 10pm)