Which statement best describes the theory of plate tectonics?

plates sometimes move closer to one another.
sections of earth that shift are part of earth’s asthenosphere.
sections of earth’s continents are in slow, constant movement.
parts of the ocean floor move as they are carried by rift valleys.

What is tan(61)? а. 1.80 b. 0.49 c. 0.61 d. 0.87

Identify the forces that contribute to the centripetal force on the object in each of the following examples: a. a bicyclist moving around a flat, circular track b. a bicycle moving around a flat, circular track c. a racecar turning a corner on a steeply banked curve

Aball tossed vertically upward from the ground next to a building passes the bottom of a window 1.8 s after being tossed and passes the top of the window 0.20 s later. the window is 2.0 m high from top to bottom. what was the ball's initial velocity? the unit vector j^ is directed upward. how far is the bottom of the window from the launch position? how high does the ball rise above the launch position?