The trait of extraversion often correlates around 50% for identical twins and around for fraternal twins.

Answer

The trait of extraversion often correlates around 50% for identical twins and around 50% for fraternal twins. It correlates around the same,  but will differ only among sexes, whether male or female.

Explanation

The Extraversion concept refers to an attitude that is characterized by concentration of interest on the external object. It is one of the 5 personality traits that I s characterized by being talkative, showing assertiveness, sociability , excitability and having emotional expressiveness.

the real answer is b. scintillation counter

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.