In an experiment, a scientist decides to study the effect of exercise on cholesterol levels in people. He studies two set of people—those who exercise every day for an hour and those who don’t exercise at all.

In this case, the statement that people who exercise for an hoour may have lower cholesterol level is HYPOTHESIS. The cholesterol level would be the DEPENDENT VARIABLE.

An hypothesis refer to a proposed statement based on prior knowledge, which is used as a starting point in scientific experimentation.

In scientific experiments, there are always two variables, independent and the dependent variable. The independent variable is the variable that is changed or controlled in a scientific experiment in order to determine its effects on the dependent variable.

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.