Which of the following best describes parent rock?
a)crushed gravel added to depleted soil to provide nutrients

b)the lowest layer of the soil horizon, containing little or no organic matter

c)high-nutrient igneous rock like obsidian, extruded from the earth’s magma

d)the primary stone sheet from which a boulder or stone originated

Which statement is true about an object that is moving in a circular motion due to centripetal force, f, when the radius of its circular motion is doubled? the new force then becomes equal to 2f the new force then becomes equal to f the new force then becomes equal to f/2 the new force then becomes equal to f2 the new force then becomes equal to 1/f