Which statement is supported by the atomic theory? A. Atoms combine to make all the substances on earth

this is not true.

B) atoms of all substances are identical in all respects..

Dalton's theory said - all atoms of one substance are identical.  Atoms of different elements differ.

Explanation:

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.

the tricuspid valve is present between right atrium and right ventricle