Run the provided unit tests and ensure that all tests pass. Manually test as follows: 1. Create a new quiz. 2. Add a new essay question to said quiz; set its response format to "plain text"*. Do not include a response template. 3. Log in as a student and attempt the quiz. In the essay response box, enter a single 0 (zero) with no leading or trailing spaces. 4. Press 'next' to move to the summary page. Verify that the question is in the "needs grading" state: its status column should read "answer saved". 5. Submit the quiz. 6. Log in as an instructor, and verify that the quiz needs grading, and has not been assigned a zero. Check for the word "complete" under the question number.