an essential facility is an input controlled by a monopolist that is essential to competitors and is effectively infeasible for competitors to duplicate. The essential facilities doctrine is that the monopolist must share those resources with their competitors on reasonable terms.

a$.$ Do you think Google$$s search engine is an essential facility? $($Address this question in the context of online retailing, where the competitors are vertical search engines.$)$

b$.$ If Google is an essential facility, how would you apply the essential facilities doctrine?