To survive hunter-gatherers changed their environment by

O burning the prairies to prevent trees from growing.

O neither (a) nor (b)

O Cultivating plants closer to where they lived.

burning the prairies to prevent trees from growing.

Explanation: hope this helps

structure is maintained and sustained by:

-cytoskeleton: gives cells coherence

-cell wall: support

-cytoplasm: shape

hope this .

explanation:

the universal gravitation equation. since the gravitational force is directly proportional to the mass of both interacting objects, more massive objects will attract each other with a greater gravitational force. if the mass of one of the objects is doubled, then the force of gravity between them is doubled.