Choose the correct description of the conveyor-like action of plate tectonics on earth
a - earth's mantle is broken up into plates that float beneath the overlying lithosphere. the bottoms of the mantle's convection cells drag the tops of the plates, making them move. this movement causes spreading in some places and subduction in others.
b - earth's lithosphere is broken up into plates that float beneath the overlying mantle. the bottoms of the mantle's convection cells drag the tops of the plates, making them move. this movement causes spreading in some places and subduction in others.
c - earth's lithosphere is broken up into plates that float on the underlying mantle. the tops of the mantle's convection cells drag the bottoms of the plates, making them move. this movement causes spreading in some places and subduction in others.
d - earth's mantle is broken up into plates that float on the underlying lithosphere. the tops of the mantle's convection cells drag the bottoms of the plates, making them move. this movement causes spreading in some places and subduction in others.

Two horizontal plates with infinite length and width are separated by a distance h in the z direction. the bottom plate is moving at a velocity u. the incompressible fluid trapped between the plates is moving in the positive x-direction with the bottom plate. align gravity with positive z. assume that the flow is fully-developed and laminar. if the systems operates at steady state and the pressure gradient in x-direction can be ignored, do the following: 1. sketch your system 2. identify the coordinate system to be used. 3. show your coordinates and origin point on the sketch. list all your assumptions. 5. apply the continuity equation to your system. nts of navier stokes equations of choice to your system 7. solve the resulting differential equation to obtain the velocity profile within the system make sure to list your boundary conditions. check units of velocity 8. describe the velocity profile you obtain using engineering terminology. sketch that on the same sketch you provided in (1). 9. obtain the equation that describes the volumetric flow rate in the system. check the units.

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

The charge on a charged sphere is: a)concentrated at its centerb)distributed uniformly throughout its volumec)clustered on its centerd)distributed uniformly over its surface