if the mass of the earth were 1/4 times the size (while radius remains constant), how would its escape velocity change?

Conservation efforts have been effective in "increasing the number of endangered species, reducing all the negative impacts of human activity, and preserving wildlife habitats".hope my answer has you : ) 

C, small, hard spheres with insignificant volumes

Answerit is not a renewable energy source;

Burned piece of steel wool does not gain mass. so only d could be true.