Answer:
A. Mass-extinction events are times in the Earth's history when few species evolve.
Explanation:
The extinction that occurred 65 million years ago wiped out some 50 percent of plants and animals. The event is so striking that it signals a major turning point in Earth's history, marking the end of the geologic period known as the Cretaceous and the beginning of the Tertiary period.
A wide range of animals and plants suddenly died out, from tiny marine organisms to large dinosaurs.
Species go extinct all the time. Scientists estimate that at least 99.9 percent of all species of plants and animals that ever lived are now extinct.
Answer:
The small pebble
Explanation:
Since the potential energy, P.E lost equals kinetic energy, K.E gained,
P.E = K.E
P.E = mgh = K.E
So, K.E = mgh where g = acceleration due to gravity and h = height of drop
Since h and g are constant
K.E ∝ m
So, the kinetic energy of the object is directly proportional to its mass. Thus, the object with the smaller mass has the lesser kinetic energy.
Since the object with the smaller mass is the small pebble, so the small pebble would have less kinetic energy as it crashes on the road at the bottom of the mountain.
Answer:
b. horizontal distance/time graph
Explanation:
d is incorrect because object is moving at the same pace the entire time
Ashleybotello0129,
What is the slant of a line on a graph called "the slope." Slopes are in math, and science. Slopes look like slanted lines start from one side and to another.
Hope this helps!
The power of a machine depend on two factors are work and time.
Option C
<u>Explanation:</u>
In science, power defined as the amount of work done in a unit time. i.e. delivering work in a rate of time or energy supply, expressed in input of work or transmitted energy divided by the time interval (t) or W/t.
Example: Some work can be done in the long run with a low-power engine or in a short time with a motor with high performance. The equation for power can be given as

