Economic systems differ according to which two main characteristics?

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?

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.

One question from a survey was "how many credit cards do you currently have? " the results of the survey are provided. complete parts (a) through (g) below. click the icon to view the survey results. (a) determine the mean number of credit cards based on the raw data. the mean is 3.113.11 credit cards. (type an integer or a decimal. do not round.) (b) determine the standard deviation number of credit cards based on the raw data. the standard deviation is 1.9111.911 credit cards. (round to three decimal places as needed.) (c) determine a probability distribution for the random variable, x, the number of credit cards issued to an individual. x (# of cards) p(x) x (# of cards) p(x) 1 0.280.28 6 nothing 2 nothing 7 nothing 3 nothing 8 nothing 4 nothing 9 nothing 5 nothing 10 nothing (type integers or decimals. do not round.)