You are planning to make monthly deposits of $420 into a retirement account that pays 8 percent interest compounded monthly. If your first deposit will be made one month from now, how large will your retirement account be in 25 years? (Do not round intermediate calculations and round your answer to 2 decimal places, e. g., 32.16.)

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?