Which is part of the niche of the american pikas? a. they climb mountains. b. they feed on dead organisms. c. they build nests far out on tree limbs. d. they find shelter between rock fragments.

the answer would be..

b. sucking

the earth is thought to have been formed about 4.6 billion years ago by collisions from a cloud of hydrogen, helium, rock, ice and other materials. these were pulled together by gravity to form objects in and around earth like- asteroids and small early planets called planetesimals.

so, the best possible answer to this question will be option d- to harden materials to form different parts of earth’s layers