Why do most earthquakes take place at tectonic plate boundaries?
a. the rock in the interior of a tectonic plate is stronger, so it does not deform.
b. earthquakes take place where the motion of tectonic plates transfers energy to rock.
c. earthquakes can only occur at places where magma can reach the surface and transfer energy to rocks.
d. earthquakes take place when one plate moves over another plate, which happens only at plate boundaries.

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advantage of using stem cells in medical research:

1.       it provides medical benefits in the fields of therapeutic cloning and regenerative medicine.

2. it provides great potential for discovering treatments and cures to a variety of diseases including parkinson disease, spinal cord injuries, diabetes, alzheimer’s disease and many more.

3. limbs and organ could be grown in lab from stem cells and then used in transplant or treat illness.

increase soil erosion                                             reduce soil erosion

cattle grazing                                                         hydroseeding

deforestation                                                         contour plowing

                                                                                planting vegetation

plant roots basically hold the top soil

together and stop soil erosion because

in such situation top soil is not removed

during flood but cattle grazing causes

soil erosion because cattle consume the

grasses and herbs and top soil is exposed.

same situation occurs because of

deforestation, the trees and plants are cut

down to expose top soil which causes soil

erosion