Chains of volcanoes -- all lined up in a row or an arc -- are often produced by plate tectonic processes: collision between two ocean plates; collision between an ocean and a continental plate; a tectonic plate moving over a hotspot; and then also volcanic activity within a continental plate with the real cause being mostly unknown. This question has you match these four processes to locations.

Extensive and unusual cold snaps have occurred here recently. is this evidence that global warming is lessening or not occurring? no—although the long-term trend is for warming, short-term weather patterns can still be variable. no—melting of glaciers and ice caps is making the oceans cooler, which can cause cold snaps. yes-- if global warming really were occurring, cold snaps wouldn’t happen. yes—due to global warming, weather patterns should be become less—not more—variable.