Generally speaking, you may submit no more than two assignments per week. Some instructors, however, may allow you to submit more assignments per week or require you to submit only one assignment per week. To find out if your instructor has different requirements, consult the information under the "Assignments" heading in the "Introduction" of your study guide. If the instructor doesn't specify anything there, then you may submit no more than two assignments per week. It's important to note, though, that it is of great benefit to you to submit one assignment at a time and to wait to receive graded assignments, so that you can read comments from the instructor before submitting subsequent assignments.