Answer:
Explanation:
More than 99 percent of all organisms that have ever lived on Earth are extinct. As new species evolve to fit ever changing ecological niches, older species fade away. But the rate of extinction is far from constant. At least a handful of times in the last 500 million years, 75 to more than 90 percent of all species on Earth have disappeared in a geological blink of an eye in catastrophes we call mass extinctions.
Though mass extinctions are deadly events, they open up the planet for new forms of life to emerge. The most studied mass extinction, which marked the boundary between the Cretaceous and Paleogene periods about 66 million years ago, killed off the nonavian dinosaurs and made room for mammals and birds to rapidly diversify and evolve.
Answer: Both passages are written for textbooks so C is youre
answer.
Explanation: this is correct
1) I
2) Heavy rains or fast-melting snow CAUSE
3) Lightning bolts FLASH
Well its not esay you have to wait for someone to get the answer then the bell to the upper right left to your sceen lets you pick :) hope it helped
