To add a calendar, in a browser logged into your google calendar, go to the left calendar bar, scroll down to "Other Calendar" and hit the + sign. Then select "From URL". Right-click (or control-click) on a URL below and select "copy link", then paste that into the form and click the "Add Calendar" button.

The event's calendar URL: 

https://calendar.google.com/calendar/ical/carnegiescience.edu_sgl0qmu38feogrc1er16n6466g@group.calendar.google.com/public/basic.ics

The deadline's calendar URL:

https://calendar.google.com/calendar/ical/carnegiescience.edu_44noqdvgrlsg0c2eh01190ejag@group.calendar.google.com/public/basic.ics