3. the author refers to a "conveyor belt " in line 13 in order to
(a) illustrate the effects of convection in the mantle
(b) show how temperature differences depend on the positions of the continents
(c) demonstrate the linear nature of the mid-atlantic ridge
(d) describe the complicated motions made possible by back-coupling
(e) account for the rising currents under certain mid- ocean ridges
4. the author regards the traditional view of the origin of the oceans with
(a) slight apprehension
(b) absolute indifference
(c) indignant anger
(d) complete disbelief
(e) guarded skepticism
5. according to the passage, which of the following are separated by a plate that is growing on both sides?
(a) the pacific ocean and the sea of japan
(b) the south atlantic ridge and the north sea ridge
(c) the gulf of mexico and the south atlantic ridge
(d) the mid-atlantic ridge and the indian ocean ridge
(e) the black sea and the sea of japan
6. which of the following, if it could be demonstrated, would most support the traditional view of ocean formation?
(a) convection usually occurs along lines.
(b) the upper mantle behaves as a dense solid.
(c) sedimentation occurs at a constant rate.
(d) sinking plates cool the mantle
(e) island arcs surround enclosed seas.
7. according to the passage, the floor of the black sea can best be compared to a
(a) rapidly moving conveyor belt
(b) slowly settling foundation
(c) rapidly expanding balloon
(d) violently erupting volcano
(e) slowly eroding mountain
8. which of the following titles would best describe the content of the passage?
(a) a description of the oceans of the world
(b) several theories of ocean basin formation
(c) the traditional view of the oceans
(d) convection and ocean currents
(e) temperature differences among the oceans of the world