Which of these can the Doppler effect be used to deduce in astronomy?
A.
the shape of the orbital path of an object
B.
whether the object is traveling toward or away from us.
C.
the chemical composition of the object
D.
the type of spectrum the object emits

What is the main purpose of completing a certification program? o a. to become eligible for a bachelor's degree o b. to receive a general education o c. to learn a specific skill for a particular career field o d. to do research in a particular career field

1) earth's crust is made up of relatively rigid plates that ride atop earth's hot, semiliquid mantle. (2) the plates are called tectonic because they're in constant motion. (3) they can move because earth's mantle is a very hot and semiliquid fluid called magma. (4) volcanoes are a result of magma rising up or erupting through a plate, particularly where plate boundaries are moving against each other. (5) also, when plates slide against each other, causing friction along adjacent plate boundaries, earthquakes frequently occur. (6) therefore, we often find volcanoes and earthquakes along plate boundaries. (7) plates may also collide. (8) when that happens, mountain ranges are formed. (9) for example, the collision of the plate carrying the indian subcontinent created the himalayan mountains when it collided with the asian plate. 2. which sentence in this passage introduces a new topic that might begin a new paragraph? a. sentence 5 b. sentence 4 c. sentence 7 d. sentence 6

Why is the road most slick when it first begins to rain? a. oils the road has absorbed begin to float. b. the water has not had time to run off. c. a higher concentration of dirt makes the road more slick. d. none of the above