Scientific research about the nitrogen cycle and water quality is mostvaluable to human populations with: afew sources of electricity. b. few sources of fresh water. c. large coastal populations. d. large amounts of farmland.

What are some possible short and long term medical concerns for crew members on longer space exploration trips

Explain how scientists use geologic time to determine the age of landforms.

Subduction zones form when an oceanic plate collides with another oceanic plate or continental plate. the continental crust is lighter and less dense than oceanic crust. continental crust's density is approximately 2.7 grams per cubic centimeter. oceanic crust is thinner and the average density is about 3.3 cubic centimeters. when the two crustal plates converge the oceanic plate always bends and subducts beneath a continental plate. once the oceanic crust subjects, the rocks are subjected to changes in heat and pressure. because of this, we would expect to find rocks in the area of a subduction. a) clastic b) igneous c) metamorphic d) sedimentary