The clock runs continuously from the point you login, so you cannot login again after 30 minutes. This means you should be prepared to finish the reading quiz in one login session. You still have 3 tries for each quiz question once you are in. For the first week, the reading quiz is open for a few days. For later weeks, it will be open only in the 24-hour period before the lecture in which a new chapter is introduced.
Next week is a lab.
Don't forget to bring your lab manual and a calculator.