Ben is interested in golf, so he visits several golf-related websites, such as the usga and the pga. unbeknownst to him, his surfing behavior is being tracked, and it's no accident that he receives several banner ads for golf products and destinations. this is called
a) market segmentation
b) search engine optimization
c) spam
d) blogging
e) behavioral targeting

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?