A nation’s average annual real GDP growth rate is 3%. Based on the "rule of 72," the approximate number of years that it would take for this nation’s real GDP to double is

The management of a private investment club has a fund of $250,000 earmarked for investment in stocks. to arrive at an acceptable overall level of risk, the stocks that management is considering have been classified into three categories: high risk (x), medium risk (y), and low risk (z). management estimates that high risk stocks will have a rate of return of 15%/year; medium risk stocks, 10%/year; and low risk stocks, 6%/year. the amount of money invested in low risk stocks is to be twice the sum of the amount invested in stocks of the other two categories. if the investment goal is to have a rate of return of 9% on the total investment, determine how much the club should invest in each type of stock. (assume that all the money available for investment is invested.)

Acompany is developing a new high­performance wax for cross country ski racing. in order to justify the price marketingwants, the wax needs to be very fast. specifically, the mean time to finish their standard test course should be less thanseconds for a former olympic champion. to test it, the champion will ski the course 8 times. the champion's times(selected at random) are 59.9 61.9 48.8 52.2 46.6 45.3 50.6 and 41.1 seconds to complete the test course. complete parts a and b below. a) should they market the wax? assume the assumptions and conditions for appropriate hypothesis testing are metfor the sample. assume=0.05. what are the null and alternative hypotheses? choose the correct answer below. b) suppose they decide not to market the wax after the test, but it turns out that the wax really does lower the champion'saverage time to less thanseconds. what kind of error have they made? explain the impact to the company of such anerror.

Employees at a library check out books to patrons. books have an isbn and a name. the library sometimes has multiple copies of the same book. books have one or more authors. a patron is an individual who has an active (non-expired) library card. for each library card, we store the person's first and last names and their address. for each employee, we store their employee id, current salary, first and last name and their address. we also store the employee id of their current manager. each time we check out a book to a patron we need to store the date of the transaction, the employee who checked out the book to the patron, and the library card of the patron. some employees have library cards. if an employee patron turns in a book late, the fine that they pay is a percentage of their salary. some employees are authors who have library cards—they are allowed to check out as many books as they like.