Describe the sources of marine debris and explain why it is a problem with global origins.

Explanation:

Marine debris consists of most anything used and discarded by humans. Winds, rivers and storms can carry this debris to the ocean from far inland, so it is not solely a case of pollution along shorelines. It is also true that oceangoing ships directly contribute to marine debris while they are at sea and not associated with any particular nation.

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.