Group the following into manmade and non-manmade (naturally occurring) items: computer, salt, fence, tree stump, hillock, lightbulb, terracotta planter, snow, wolves, tablecloth, periodicals, museum

Manmade: computer, fence, lightbulb, terracotta planter, tablecloth, periodicals, museum
Non-manmade: salt, hillock, tree stump, snow, wolves