Your friends own a lawn care business. they own their own equipment and trailers to transport it. eventually they buy out another local lawn care company and double their customers. this is an example of ending an oligopoly creating an oligopoly vertical consolidation horizontal consolidation

Google started as one of many internet search engines, amazon started as an online book seller, and ebay began as a site where people could sell used personal items in auctions. these firms have grown to be so large and dominant that they are facing antitrust scrutiny from competition regulators in the us and elsewhere. did these online giants grow by fairly beating competition, or did they use unfair advantages? are there any clouds on the horizon for these firms -- could they face diseconomies of scale or diseconomies of scope as they continue to grow? if so, what factors may limit their continued growth?