Which statement best describes two events that occur at a convergent boundary where one plate moves under another a. frequent earthquakes may occur volcanic activity may be common b. it will be rare for earthquakes to occur and volcanic activity will be minimal c. earthquakes will be frequent but volcanic activity will be maximum d. a trench may fork but earthquakes and volcano activity will be minimal

A. Frequent earthquakes may occur volcanic activity may be common.

When the plates of the continents and oceans collides, the thin and dense oceanic plate submerged under the thick and less dense continental plate. This process is called as subduction. As the oceanic plate submerged down the earth crust it is exposed to the hot magma. The melting of the subducted plate occurs and this results in the high intensity volcanic eruption and  frequent earthquakes.  

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.