How do externalities encourage/discourage descions that we make?

Beta coefficients and the capital asset pricing model personal finance problem katherine wilson is wondering how much risk she must undertake to generate an acceptable return on her porfolio. the risk-free return currently is 4%. the return on the overall stock market is 14%. use the capm to calculate how high the beta coefficient of katherine's portfolio would have to be to achieve a portfolio return of 16%.

Anewspaper boy is trying to perfect his business in order to maximize the money he can save for a new car. daily paper sales are normally distributed, with a mean of 100 and standard deviation of 10. he sells papers for $0.50 and pays $0.30 for them. unsold papers are trashed with no salvage value. how many papers should he order each day and what % of the time will he experience a stockout? are there any drawbacks to the order size proposed and how could the boy address such issues?

If the economy were in the contracting phase of the business cycle, how might that affect your ability to find work?