Consider a market with four firms. suppose the first firm has a 49% market share, the second firm has a 35% market share, the third firm has a 15% market share, and the fourth firm has a 1% market share. using the herfindahl-hirschman index (hhi), what is this market's level of concentration?

Consider a treasury bill with a rate of return of 5% and the following risky securities: security a: e(r) = .15; variance = .0400 security b: e(r) = .10; variance = .0225 security c: e(r) = .12; variance = .1000 security d: e(r) = .13; variance = .0625 the investor must develop a complete portfolio by combining the risk-free asset with one of the securities mentioned above. the security the investor should choose as part of her complete portfolio to achieve the best cal would be a. security a b. security b c. security c d. security d