George is lifting weights. he starts by doing biceps curls which involves his elbows. his elbow is able to bend because the humero-ulnar joint is a joint. sam is doing leg presses, his knees as he pushes against the weights. the knee joint is primarily a joint, though it can act as a condylar joint when flexed. meanwhile, jane is doing "lat pulls" by pulling downward on a weighted bar. this movement involves of her arms. her shoulder joint is a joint, allowing a wide range of movements.

George is lifting weights. He starts by doing biceps curls which involves flexing his elbows.  His elbow is able to bend because the humero-ulnar joint is a hinge joint.  Sam is doing leg presses, extending his knees as he pushes against the weights. Meanwhile, Jane is doing "lat pulls" by pulling downward on a weighted bar. This movement involves adduction of her arms.  Her shoulder joint is a  ball-and-socket joint, allowing a wide range of movements. 

the answer would be b

explanation:

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