the $510$b finance company is considering an investment but would like more information first. based on the following data what is the standard deviation of returns? state of economy recession normal boom probability of state of economy $\mathrm{.}22\mathrm{.}47\mathrm{.}31$ rate of return if state occurs $-\mathrm{.}090\mathrm{.}105,\mathrm{.}215$