Add SDA policy

Author: saisha-r

syllabus.md

@@ -123,6 +123,9 @@ Due dates for all assessment and evaluation components will be posted on the cou
 
 You can expect that grading of the evaluations will be quite strict. For all evaluations, **late work will be penalized 2% per hour**, with the clock starting the minute after the deadline has elapsed. **Requests for extensions will only be considered prior to the due date**.
 
+### Student Declaration of Absences (SDAs)
+If you are unable to complete work by the deadline, you can submit a [Student Declaration of Absence (SDA) form](https://cdn.dal.ca/content/dam/dalhousie/pdf/campuslife/Health%20and%20wellness/FINAL%20Student%20Declaration%20of%20Absence%20Form.pdf) to the instructor via email. These must be submitted before the deadline. You may submit up to 2 SDAs per term. If situations arise that make you unable to meet deadlines after you have already submitted 2 SDAs, please discuss these — ideally in advance — with the instructor.
+
 ### Assignments
 These are coding assignments that you will complete, based on neuroscience data. There is an assignment due approximately every second week, except weeks when projects are due. The first assignment is mandatory for everyone, and it's important because it will teach you how to access course materials and use the tools required for the rest of the course. All of the other assignments are mandatory, however --- if and only if you submit *all* of the assignments --- the grade on the assignment you did worst on will be dropped (see table below).