21. While digging, a person found that most of the rocks were igneous rock. What can be concluded?
a. The rocks were probably carried there by ancient people.
b. The area was once covered by an ocean.
C. A glacier passed through at one time.
d. A volcano was nearby at one time.

Explain why components that are naturally found in air can be considered air pollutants.

Study the image. which feature is modeled in the diagram? check all that apply. 1 a convergent boundary is formed. 2 continental plates are colliding. 3 two plates are forming a divergent boundary. 4 continental plates are sliding past each other. 5 several mid-ocean ridges are formed on earth’s surface.

8. is a technique that uses the images from several telescopes to produce a single image. a. reflection b. interferometry c. radiation d. refraction