Hi holly0918, exam 250398 is the Writing Process webinar. This is a live, 90 minute class that students must take. Similarly, exam 250399 is the Research, Writing, Citation and Documentation webinar. These classes need to be registered for on your student portal. Take a look at this document: English Composition Webinars: FAQ. This will help answer all your webinar questions.
Let me know if you have any other questions.
Best of luck in your studies,
Rianna J.
English Instructor