When there is an externality in a market the externality will move the market to an economically efficient equilibrium?

The framers of the us constitution created a system of government that established branches of government set forth the powers of such a branches and placed limits on those powers what are the benefits of such a system? are there any problems associated with such a system?

Acrosswalk_when there are no pavement markings.

Stock a has a beta of 1.2 and a standard deviation of 20%. stock b has a beta of 0.8 and a standard deviation of 25%. portfolio p has $200,000 consisting of $100,000 invested in stock a and $100,000 in stock b. which of the following statements is correct? (assume that the stocks are in equilibrium.) (a) stock b has a higher required rate of return than stock a. (b) portfolio p has a standard deviation of 22.5%. (c) portfolio p has a beta equal to 1.0. (d) more information is needed to determine the portfolio's beta. (e) stock a's returns are less highly correlated with the returns on most other stocks than are b's returns.