FIGURE $6\mathrm{.}1$ Portfolio risk as a function of the number of stocks in the portfolio

A: Firm$-$specific risk only

B: Market and unique risk $\backslash$table$[[,$FIGURE,$6\mathrm{.}2,$Portfolio risk as a function of the number of stocks in the portfolio$]]$

Source: Authc. $q,..$nalysis $22,$

September $1987.$ This plot uses data over the $5-$year period $2010-2014.$ FIGURE $6\mathrm{.}4$ Investment opportunity sets for bonds and stocks with various correlation coefficients

Explain each figure with your interpretation as concisely as possible.