Which of the following did not contribute to the staggering number of technological breakthroughs that have changed the face of marketing in the 21st century in the last decade?
online retailing
the personal computer
smartphones
social media

Seattle bank’s start-up division establishes new branch banks. each branch opens with three tellers. total teller cost per branch is $96,000 per year. the three tellers combined can process up to 90,000 customer transactions per year. if a branch does not attain a volume of at least 60,000 transactions during its first year of operations, it is closed. if the demand for services exceeds 90,000 transactions, an additional teller is hired and the branch is transferred from the start-up division to regular operations. required what is the relevant range of activity for new branch banks

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?

David consumes two things: gasoline (g) and bread (b). david's utility function is u(g, b) = 10g^0.25 b^0.75. use the lagrange technique to solve for david's optimal choices of gasoline and bread as a function of the price of gasoline, p_g, the price of bread, p_b, and his income m. with recent decrease in the price of gasoline (maybe due to external shock such as shale gas production) does david increase his consumption of gasoline? for david, how does partial differential g/partial differential p_g depend on his income m? that is, how does david's change in gasoline consumption due to an increase in the price of gasoline depend on his income level? to answer these questions, find the cross-partial derivative, |partial differential^2 g/partial differential m partial differential p_g.