Typos in part06-2 writing files

<img width="1332" height="309" alt="Image" src="https://github.com/user-attachments/assets/4f0ad6bf-2221-4d48-88f4-cf5bef6888b8" />

The text is "whch" instead of "which"

<img width="1347" height="412" alt="Image" src="https://github.com/user-attachments/assets/801e7e6d-8819-462a-b07e-ea75ef99a776" />
The text is "exatly" instead of "exactly"