The organism shown is a free-living one that is anchored to the bottom of ponds and streams during the first part if its life cycle. what is the common name of the group to which this organism belongs? a. comb jellies b. arthropods c. echinoderms d. cnidarians

Which plate boundary causes plates to collide forming mountain ranges, volcanoes, and island arcs? give an example of this type of plate boundary. 2. at which plate boundary do rifts and mid-oceans ridges form? give an example of this type of plate boundary. 3. at which plate boundary do plates slide past each other while moving in opposite directions? give an example of this type of boundary.