0. [Warmup. Don't hand them in.] Exercises 2.1, 2.3, 2.4, 2.5
1. Do Exercise 2.6b. Explain why your grammar generates the desired language.
2. Give the state diagram of a pushdown automata recognizing the language of Exercise 2.6b. Do not translate the grammar you obtained from the previous problem. Design your PDA from scratch.
3. Do Problem 2.47a.
4. Do Problem 2.47b. Use at most 3 variables and at most 7 rules.
5. Do Exercise 2.9. If your grammar is ambiguous, pick a string in the language and show how it can be derived in more than one way.
6. Do Exercises 2.14. For each step you apply, you should describe its purpose. You may write up your work as in Example 2.10, except that you should not include in the new grammar the rule you have just eliminated.
Extra credit. Do Problem 2.21 or Problem 2.23.