(i will give a brainliest) describe the practices of firms in various markets, such as perfect competition and monopoly.

Uestion 7 you hold a portfolio consisting of a $5,000 investment in each of 20 different stocks. the portfolio beta is equal to 1.12. you have decided to sell a coal mining stock (b = 1.00) at $5,000 net and use the proceeds to buy a like amount of a mineral rights company stock (b = 2.00). what is the new beta of the portfolio?

Ursus, inc., is considering a project that would have a five-year life and would require a $1,650,000 investment in equipment. at the end of five years, the project would terminate and the equipment would have no salvage value. the project would provide net operating income each year as follows (ignore income taxes.):

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?