After a volcanic eruption, lava flowed over an area and then cooled to form a thick layer of new rock. One thousand years later, a thriving forest with diverse flora and fauna is found in that area, even though evidence suggests that several large forest fires have occurred.

Which statement best describes what happened?

Secondary succession occurred, followed by several primary successions.
Only secondary successions occurred.
Primary succession occurred, followed by several secondary successions.
Only primary successions occurred.

If an inclined plane is 5 m long and 2 m high, what is its mechanical advantage? a. 2.5 b. 3 c. 7 d. 10

The key to stability is feedback between the reservoir and the fluxes into and/or out of the reservoir. assume that the rate of outflow from a reservoir depends on the size of the reservoir according to the following relationship: outflow rate= k x (size of reservoir), where k is a constant. a reservoir of water has a volume of 5000 liters, and the rate of outflow at steady state is 25 liters per minute. what is k? (give both the numerical value and its units.) what is the residence time? what is the relationship between k and the residence time?

Aballet student who learns with the of his instructor is demonstrating learning.