Which of the following is a strong base?
a. h2o
b. NH3
c. CaCo3
d. NaOh

Subduction zones occur on earth where dense oceanic crust dives under more buoyant continental crust. these boundaries are characterized by a deep ocean trench next to a high continental mountain range, large numbers of earthquakes and volcanoes. all of this is further evidence for the a) big bang theory b) origin of the species eliminate c theory of plate tectonics d theory of natural selection 4 sedimentary rocks found high in the himalayen mountain

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Is a pencil falling to the floor anon contact force, a force, or a contact force