| 1. | Modify the program in the Example to program Bill to pick up beepers if the wall sections are removed. |
| 2. | Write a new instruction for Bill named empty-beeper-bag. After Bill executes this, his beeper bag should be empty. |
| 3. | Write a new instruction for Bill named go-to-origin. This should position Bill on 1st street and 1 st avenue regardless of his initial position and the direction he is facing. |
| 4. | Write an instruction that faces Bill east if he is on a corner with an even number of beepers, and faces him west if he is on a corner with an odd number of beepers (zero is considered an even number). |
| 5. | Program Bill to run a Steeplechase. In this race the hurdles are arbitrarily high and arbitrarily wide. The finish is marked by a beeper, which Bill must pick up before turning himself off. |
