Which of the following substances increases in quantity during repititive muscle contraction during oxygen deficti ?​

Lactic Acid

Explanation:

Lactic acid builds up during strenuous movement combined with lack of sufficient oxygen.

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.