Josiah uses a pencil called Brand A. He has pencil smears on his paper every time he completes an assignment and he hates this! Caleb is using a pencil called Brand B. Josiah notices Caleb never has smears on his paper. Josiah wonders if it's the brand of pencil that's keeping Caleb from getting smears on his paper. He decides to borrow Caleb's pencil and test the brand against his to find out. Hypothesis:

What is another variable that Josiah could test in this situation as a 2nd experiment?

the electromagnetic spectrum includes, from longest wavelength to shortest: radio waves, microwaves, infrared, optical, ultraviolet, x-rays, and gamma-rays.

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