Which of the following are considered pure substance? ?
a. element
b. compound
c. homogenous mixture
d. heterogeneous mixture

What role does weathering have in shaping earth’s surface? a) it allows sediments to fall out of a medium. b) it sediments settle on a new surface. c) it breaks down older material into sediments. d) it transports sediments to a different location. will give brainliest, answer quickly.