Residence Time in the Ocean Is

Residence time in the ocean is

A) the average time an atom remains in a system such as the ocean or a human body.
B) the same as a Milankovitch cycle.
C) the amount of time a tropical storm can remain on land before dying out.
D) the average length of time a glacier stays in one place before it begins to move.
E) the time it takes for one liter of water to move one horizontal mile in an aquifer.