According to the video, what sparked a rejuvenation of interest in, and subsequent repairs to, notre-dame cathedral in the mid-1800s?
the french revolution
the publication of the hunchback of notre-dame
the catholic revolution
the increased interest in gothic architecture

interdependence is when all participating groups and individuals depend on each other. if you depend on one anothers goods, you end up trading in order to get the items you're looking for. (for ex: if i have food and you have water, we trade in order to depend on each other to live)

b. ensure mutual protection from communism.

.