What were the oldest living things from 3.5 billion years ago like?

Big.

Explanation:

Most of the animals there were most likely really big. like turtles and bugs.

c is the answer : )               your welcome

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.