Each year, a cyber cafe charges its customers a base rate of $25, with an additional $0.30 per visit for the first 50 visits, and $0.10 for every visit after that. How much does the cyber cafe charge a customer for a year in which 72 visits are made?

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